"... but then that part [i7-4790] has a lower maximum clock of 4.0GHz, so on the whole the i7-4790K is still going to be faster."
Apparently not, considering your stress tests. Since the CPU is so thermally limited, it can't be overclocked past or boost higher than 4GHz, which means that you might as well save the cash and get the non-K.
Despite what Clevo claims about the thermal interface used, I'd like to see you guys open up the laptop and inspect what kind of job they did. If not a good one, repasting the CPU and retesting would surely be a welcome follow-up.
I agree, and mentioned the same in the original review. The 4790K is not worth the cost because they already run warm. A slightly slower i5 would perform nearly the same due to not throttling as often.
I would like to see the headroom on overclocking one of these with an i5k skew now that you mention it. I mean if this is a gaming laptop, and it is using desktop sku processors (No dual core i5 issues) then the i7 was a waste of money to begin with.
The worst part about all of this? Is that I never even thought about it until I read your comment.
Hey Jarred, is it possible to get one of these with a Devils Canyon i5k for testing? I imagine probably not, but it doesn't hurt to ask! :D
@Assimilator: Remember the max turbo is 4.0 GHz on i7-4790, and you're not going to hit max turbo with all cores active. Hence, my assumption is with 4790 you will actually clock closer to 3.6GHz vs. ~3.9GHz on 4790K. And if you max out the fan speed, of course you're going to hit 4.1GHz on the 4790K even under stress conditions.
Regarding the i5-4690K, it's a reasonable alternative that will save $100 or so. How much slower would it be? Well, unless it overclocks to 4.0-4.4GHz, the 4790K will certainly be faster. Stock clocks are 3.5-3.9GHz. If you're buying a Eurocom P5 Pro, the the i7-4790 and i5-4690K are the same price while the i7-4790K is $91 more. On a top performance $2500+ notebook (assuming 16GB RAM, 512GB SSD, 980M) is it worth saving $91 on the CPU? I don't think so.
Apologies for not being clear, the money savings was just icing on the cake. Just wasn't sure if you could use an i5 in place of the i7 while still being able to feed the GPU. Maybe allow for a bit more thermal headroom or at least less long term stress from some possibly lower sustained temps.
are i5's having a hard time feeding 980's in desktops? If not then it should have no problem feeding a 980m right?
Top end i5's are actually suggested for desktop who primarily game, as there is generally no frame rate increase going from the i5 to the i7. All you are getting is essentially hyperthreading, as all of the haswell chips overclock to similar levels (if they are unlocked).
Don't forget that Anandtech has 0 clue what proper thermal pasting is, as well as what tweaking even is, so they will tear anything down that exceeds their standard knowledge of "power on and push"
Assuming the system can stably undervolt of course, which isn't guaranteed. I'll give it a shot and see. Any suggestion on a suitable undervolt offset?
Well, -100mV is *trying* to run my stress test. It crashed without max cooling (just Tomb Raider, not the system). I maxed the fan and tried again; after a minute or two the system restarted. Guess I'll try -50mV now.
I bought a barebones Clevo P770ZM equipped with a 980M and added a 4790K. The 4790K seems pretty receptive to undervolting based upon my experiences and experiences of many others as posted in the TechInferno forums. Some people have managed to get as high as 5 GHz with 4.7 GHz more typical. However, for such high speeds, the fans must be run on max, which is accomplished with the hotkey FN + 1. I also suspect those higher speeds may require a delid *shrug*. While I personally wouldn't run a desktop processor in a laptop with those overclocks, it is possible.
Are you saying people are hitting 4.7GHz under a stress test? Because I can get the system to boot at 4.6/4.7GHz but as soon as I start stress testing it's a no go. Trying for -50mV on the CPU now as -100mV didn't work out.
So, take it as you will: I recommend starting with -25mV at a time. First, lock the cache ratio multiplier to 40 (hereinafter stock multiplier). Start at -30 to -50mV under on the cache ratio (note - leave all adaptive voltages set to adaptive and default. If you try setting the adaptive voltage like a desktop, then set an offset on top of it, some weird readings can be had in programs like HWmonitor for both the ring voltage and the IA voltage offset. As I haven't figured this out yet, I'd recommend staying away from it until later if you want to play). Then reduce the voltage from that amount by 25mV until no longer stable in XTU stress test. Then bring it up by 5mV intervals until stable for the test of your choice. What you may want to explore is other tests utilizing the AVX2 instruction set as this is the cause of the extreme heat on Haswell with the newer prime95. Alternatives for lower heat tests are prime95 version 26.6. If you want AVX ( but not AVX2) you can use prime95 27.7 or 27.9. These give you prime95 stability without the insane heat for the platform. Alternatively, loop x264 for testing the AVX set. Either way, the idea is to have the laptop under normal stress situations, not insane heat situations unless you do certain encoding that requires it. Then it is necessary. You just want fully stable. After you find the stable cache ratio, repeat for the core clocks. Lock the multiplier for all cores to be the same and start offsetting. (note - if the C states are enabled, dynamic voltage offset must be true for every possible C-state voltage request. Think of it like a totem pole with set notches in it. These notches correlate to stock voltages for every C-state, including C0 (load). The offset is like cutting that much voltage off the bottom of the totem pole. This means instability may arise entering or coming out of C-states. Just be aware of it). Once you have the Core and Cache offset stable to your liking, then test away with what you like. Benchmark, do your every day tasks, etc. Be aware, it may pass any number of stress tests and still have slight instability. Just increase the Core voltage and keep going. As long as you are under 4.4 ghz, you shouldn't have a need to change the cache voltage for stability (in my experience with my machine, yours may differ). I run everyday at undervolt -65mV Core, -110 Cache (0.995 Vcore) at 40 multiplier all cores and stock cache multiplier. That is low 70s auto fan for XTU and WPrime testing. After I get my pads here, gelid gc-03 extreme, and CLU, I intend on delidding and going beyond (the 4.9GHz was on a delidded CPU). 4.2 should be easy on max fans also in the 70s on lighter stress testing (meaning other than prime95 v.28 or OCCT 4.4.1).
Also, first try to get 4.5 stable in lower stress test conditions first, then see if the thermal room will allow for 4.6 or 4.7. Unless you won the Haswell chip lottery, 4.6 and 4.7 without delidding will not likely be possible, but up to 4.5 should be if you don't mind seeing temps in the 90s. I am delidding solely to get 4.4-4.5 under autofan in the 70s. I, personally, apply two different settings: work mode and play mode. Work mode is autofan and temps in the 70s. This leaves plenty of thermal headroom and allows for it to be quieter in public, etc. The other is game mode. This is 70s to low 80s at more stress than I do for work mode. It is important to remember that this is a desktop chip with a Tcase of 74.4 degrees Celsius. Laptops are extremely closed cases, meaning that the heat around is nearly what the CPU temp is, meaning 80 should be your upper max for everyday operation (or at least is how I treat my chip for longevity). You will find different offsets on Dynamic Voltage Offset (Vcore offset) depending on the multiplier used. This is because Intel guarantees all chips will function (up to max turbo 4.4GHz) at the stock voltage applied for each multiplier. Each chip is unique and some can use less voltage at a specified multiplier. So the offset will vary for the Vcore depending on the multiplier.
Also, there are three types of overclocking: Static, Adaptive, and Dynamic Mode Overclocking. Dynamic Mode Overclocking is what is commonly applied to laptops. This allows for lower voltages while allowing for programs to request more than what the offset normally applies for voltage without crashing the system. Benefit - lower overall voltage (meaning lower heat). Drawback - stability testing sucks, C-states are affected by the voltage offset. Static - applies a set voltage all the time. Benefit - stable under any draw. Drawback - Voltage applied all the time which increases overall heat, requires much higher voltages than any other method of overclocking. Adaptive Overclock - Adjusts only the turbo voltage requests on the CPU. Benefits - Does not affect the voltage of C-states, it only affects the Turbo Voltage (acts as a separate VID state above all C states); allows CPU to request voltages beyond the max turbo voltage set by user. Drawbacks - allows CPU to request voltages beyond the max turbo voltage set by user which causes extreme power draws when running synthetic benchmarks like Prime95, OCCT, etc. Because of these, Dynamic Mode Overclocking is the preferred method of overclocking on laptops. But see: http://forum.notebookreview.com/threads/guide-to-h... . I have not been able to replicate his findings/results with adaptive overclocking while performing Dynamic Mode Offset. Further, I run my CPU under stress at a dynamic offset causing the Vcore to be .0.995V, whereas with setting the Adaptive voltage to .950 Vcore, it still supplies 1.055V Vcore under stress conditions (as with the heat that comes with it). This may be different once the voltage required is greater than Intel's stock voltage at a set multiplier, but for voltages used before that point, it would seem that Dynamic Mode Overclocking provides the lowest voltage to the CPU, and thereby provides the lowest possible heat for the 4790K without advanced cooling solutions (delidding, etc.) for this device.
Not true. 4.6 and 4.7 was prime95 v.28.5 stable. See http://forum.notebookreview.com/threads/official-c... Now, this immediate testing was XTU, but prime testing did happen (see page 255). Superkyle1721 continued his delidded OC journey to page 258. I, personally, have prime tested and had my web surfing (I'm a tab whore) BSOD my system on Prime stable. This means prime stable isn't the be all end all when firefox brings prime stable to it's knees (over 300 tabs at a time is normal). So go on with prime, it is hot and doesn't guarantee stability for my use. I look at prime95 27.7/27.9 for my AVX testing (10 degrees hotter than others rather than 20 tested by AVX2 instruction set found in prime95 v.28.5 and OCCT4.4.1.) as well as x264 loop. I start with XTU because it is about the easiest to pass. Then move onto Wprime and BurnIn Test (Passmark). After it is stable in these, I do an x264 loop. Then I do either prime95 26.6 (no AVX) or prime95 27.7/27.9 (if testing AVX and not AVX2). Then I do massive blend testing. Heat is not what tells me I'm stable because a pass in prime still fails my browsing habits, needless to say more of my visualizations. It is a great tool at pointing out instability - I admit it is one of the best. But choosing something that is one of the best at what it does that has been made impracticable by heat considerations is ludicrous! If you want a full list of my stress testing programs and benchmark programs, I can get that to you. But Prime95, due to its heat with AVX2, has made itself impractical for most uses and few people do activities that push their processor to those limits. So the average overclocker is building in a 20 degree headroom on his/her system that he/she will never take advantage of. Does that make sense? NO, IT DOES NOT!!! Some people encode, run multiple virtual machines simultaneously, etc. and push their processors to the max on temp reaching the same as Prime95 small FFT. Those people have a need for this to set their thermal limits of their systems to their liking. But for the rest, you set prime95 small FFT to 80 and never see the processor break 65 under load. Why? It is time to start rethinking the Prime or nothing standard. Yes, testing with multiple stress tests to assure stability takes longer. But you can set the temps according to your usage, not some theoretical max that you never push in your use of your machine. Believe it or not, I have had 4.2GHz prime95 stable small FFT with thermal throttle to 4.15 with bad heatsink contact on one of four corners with MX-4. I have had it 4.5 stablish with thermal throttle to 4.42 with XTU and WPrime (I will not prime test if weaker tests thermal throttle, that is ridiculous to consider and you should have your head examined if you think otherwise). Superkyle1721 had, after delidded, got 4.4 prime95 for 20min. large FFT with temps never above 92 degrees. Granted not as hot as small FFT, but still a fair score. So please read and research before saying those guys are not prime stable as if that is the only stability that matters. Open your mind to new possibilities please.
The problem with desktop CPUs in a laptop is that the cooling is WAY less efficient due to the use of a heatspreader. Laptop CPUs have the exposed die with no heatspreader in the way so you have a much shorter and more efficient path for heat to flow and cooling to be effective. Combine that with the fact that the laptop CPUs are binned for much higher efficiency than desktop parts and it starts to explain why laptop CPUs make more sense in laptops :) They do cost more as a result, but pretty much since Sandy Bridge, there has been very little reason to bother with desktop parts in laptops, clock for clock the performance is identical.
An Intel Core i7 4810MQ can turbo up to 3.8 GHz vs 4 GHz for a 4790 or 4.4 Ghz for the 4790k. At the same time power usage is HALF resulting in much better thermals and more reliable performance as well as gaining the benefit of technologies like Optimus. If you are really that hell bent on CPU performance for gaming in a laptop than money is clearly not a limiting factor so get the 4940MX can clock it well past the stock clocks of a 4790k (this is very doable). At this class of laptop the premium for the extreme CPU is not as bad as it sounds, adding $800 to a $3000 laptop is doable for the people buying $3000 laptops usually. I have played that game in the past, getting the extreme CPU and overclocking the hell out of it in a top tier gaming laptop and after getting benchmarking out of my system (which took about 3 years) I now usually go for the entry level quadcore to have all the threads I want and not pay out the nose for marginally higher clocks.
But that DID require putting my laptop in a chest freezer to cool the CPU - 1.5V ran pretty hot. At the end of the day though, the crappy nvidia chipset in the original M17x was my limiting factor with my Ram and not the CPU.
To be honest, laptops probably don't have the margins for overclocking that a desktop would.
For the desktop CPU, it is already pretty hot to begin with. You might be able to knock 15-20C down by delidding that 4790k, much like a desktop. The problem is, with a desktop you can use a giant cooler like the Noctua D15, or water cool. You cannot with a laptop.
GPUs have similar problems. Large triple slot coolers and water blocks are available - indeed they are made specifically for desktop overclocking. There's no way to do that in a laptop. It just isn't possible.
Did you see the GPU temps? With a 20% overclock it only reached around 77C, which is cooler than many stock coolers on similar desktop cards.
CPU temps are bad though. I think the problem is that clevo went with a combined GPU/CPU heatsink for this laptop, which is something they have not done before. While this sounds good at first, it makes having good die contact on both CPU and GPU nearly impossible without a large amount of flex in the heatsink, which the P750ZM heatsink does not have.
Apples to oranges. Maxwell is a pretty cool running chip on desktops too. If you are comparing the 980M to the AMD 290X, then yes, the desktop chips are hot in comparison. But remember, we should be comparing the 980M to a desktop Maxwell, and this is a chip that has 1/4 of the units stripped (so 1536 out of 2048 active) compared to the desktop part, which is already pretty cool running.
A delid as I said might solve the problem partly like in desktops of the 4790k, but either way, there isn't much OC headroom in that chip even with the delid.
The CPU runs cooler and the battery life is better, should you ever need it. It is somewhat slower, but not by much. Plus newer versions with an IPS screen are available - I just wish Anandtech had reviewed it with the IPS screen.
I just wish that instead of overclocking, that a full 2048 version of the 980 were available, running at a lower clockspeed. My wet dream would be the big 3072-Titan X die severely underclocked on a laptop, but that would never happen for various reasons.
Yeah full 2048 would rock. I am 100% convinced that the only reason it just has 1536 running is so Nvidia can release a fully enabled chip in the future and say they have a new, faster card.
Actually, looking at the combined CPU and GPU temps, it's pretty obvious that system is more or less maxed out thermally.
The CPU is pegged at 95-99C, and the GPU is similarly pegged at 77C. When the GPU clock is raised is that the CPU clock goes down, so "overclocking" here merely trades CPU clocks for GPU.
Not that it's a bad idea really, as shown by the game benchmarks, but it does show that there is close to no headroom at all in the Clevo's combined thermals.
I think overclocking with today's hardware is stupid, I have no interest in it. I tend to agree with Nvidia on OC.
However, that doesn't mean they should go so far as to BLOCK people from being able to do it. Ultimately once they've bought it, it's their choice. At least it should be.
Have OC void the warranty and be done with it. There's no reason to do anything more than that. "You wanna overclock? Fine, do so at your own peril. We wash our hands of you".
This attitude would bring their position from being the right one for 99.9% of the market to 100%.
Nice work Jarred, glad to see authoritative sites like AT starts to acknowledge OC on mobile GPU! Although you still didn't test with USB 3.1 ports on this machine (so you didn't have peripherals available?)... and in the future I would recommend when you are doing stress tests, just run Prime95 and and Furmark instead for maximum heat on the system. Running Prime95 and tombraider at the same time actually reduces CPU load, because floating point calculation requires much higher work load than game physics. That aside you did a fantastic job! Funny when you noted on potential reasons why Nvidia blocked OC, every generation some cards are just rebrands of old cards with a slightly higher clockspeed. So essentially you can get a free upgrade yourself when you do that, and OC damaging the gpu might not as much of a threat if Nvidia is doing it themselves every generation LOL
I disagree with your choice of tests. Max heat isn't the goal with a laptop UNLESS YOU LITERALLY PUSH THE HEAT ON YOUR MACHINE DAILY FOR ITS INTENDED PURPOSE. I had to change the way I thought about overclocking when I came to a laptop. It isn't about max heat like desktop testing (which now reflecting on it is a little stupid if you never do real world activities that push it like that). You want to test max heat for real world type tests. Anything you may do (x264 for avx encoding, etc. There is a long list of stress tests that fully stress the machine without giving synthetic instruction sets to push the hardware to a heat max.). Also, Furmark and Kombuster are vbios blocked in the premamod bios.
Nah, this is no way advisable as longevity and reliability will be sacrificed. It's rare that notebook cooling have been over engineered and mobile GPUs are notorious for deteriorating solder joints which can't be permanently fixed cheaply.
I seem to be missing something, who gets power supplies rated based on input wattage, and not output? EVERY laptop power supply I own is rated on the power supplied to the machine. It makes no sense to me to rate the input.
I noticed that in this article, for the stock configuration, the GPU temp for the P750ZM stayed below 70 C roughly. However in the full review of the P750ZM, the GPU temp that was shown hovered around 75 C. Can you please comment on the discrepancy?
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The_Assimilator - Friday, March 20, 2015 - link
"... but then that part [i7-4790] has a lower maximum clock of 4.0GHz, so on the whole the i7-4790K is still going to be faster."Apparently not, considering your stress tests. Since the CPU is so thermally limited, it can't be overclocked past or boost higher than 4GHz, which means that you might as well save the cash and get the non-K.
Despite what Clevo claims about the thermal interface used, I'd like to see you guys open up the laptop and inspect what kind of job they did. If not a good one, repasting the CPU and retesting would surely be a welcome follow-up.
Stuka87 - Friday, March 20, 2015 - link
I agree, and mentioned the same in the original review. The 4790K is not worth the cost because they already run warm. A slightly slower i5 would perform nearly the same due to not throttling as often.Refuge - Friday, March 20, 2015 - link
I would like to see the headroom on overclocking one of these with an i5k skew now that you mention it. I mean if this is a gaming laptop, and it is using desktop sku processors (No dual core i5 issues) then the i7 was a waste of money to begin with.The worst part about all of this? Is that I never even thought about it until I read your comment.
Hey Jarred, is it possible to get one of these with a Devils Canyon i5k for testing? I imagine probably not, but it doesn't hurt to ask! :D
JarredWalton - Friday, March 20, 2015 - link
@Assimilator: Remember the max turbo is 4.0 GHz on i7-4790, and you're not going to hit max turbo with all cores active. Hence, my assumption is with 4790 you will actually clock closer to 3.6GHz vs. ~3.9GHz on 4790K. And if you max out the fan speed, of course you're going to hit 4.1GHz on the 4790K even under stress conditions.Regarding the i5-4690K, it's a reasonable alternative that will save $100 or so. How much slower would it be? Well, unless it overclocks to 4.0-4.4GHz, the 4790K will certainly be faster. Stock clocks are 3.5-3.9GHz. If you're buying a Eurocom P5 Pro, the the i7-4790 and i5-4690K are the same price while the i7-4790K is $91 more. On a top performance $2500+ notebook (assuming 16GB RAM, 512GB SSD, 980M) is it worth saving $91 on the CPU? I don't think so.
Refuge - Friday, March 20, 2015 - link
Apologies for not being clear, the money savings was just icing on the cake. Just wasn't sure if you could use an i5 in place of the i7 while still being able to feed the GPU. Maybe allow for a bit more thermal headroom or at least less long term stress from some possibly lower sustained temps.are i5's having a hard time feeding 980's in desktops? If not then it should have no problem feeding a 980m right?
extide - Saturday, March 21, 2015 - link
Top end i5's are actually suggested for desktop who primarily game, as there is generally no frame rate increase going from the i5 to the i7. All you are getting is essentially hyperthreading, as all of the haswell chips overclock to similar levels (if they are unlocked).Goodstorybra - Tuesday, March 24, 2015 - link
We have people on NBR already running @ 4.5ghz on stress testing @ 77C so that fear of heat is moot at this point.Goodstorybra - Tuesday, March 24, 2015 - link
Don't forget that Anandtech has 0 clue what proper thermal pasting is, as well as what tweaking even is, so they will tear anything down that exceeds their standard knowledge of "power on and push"nunomoreira10 - Friday, March 20, 2015 - link
Undervolting the processor with an ofsett if possible could really help lower the temperature, and more extreme, a deliding would also help a lot.JarredWalton - Friday, March 20, 2015 - link
Assuming the system can stably undervolt of course, which isn't guaranteed. I'll give it a shot and see. Any suggestion on a suitable undervolt offset?JarredWalton - Friday, March 20, 2015 - link
Well, -100mV is *trying* to run my stress test. It crashed without max cooling (just Tomb Raider, not the system). I maxed the fan and tried again; after a minute or two the system restarted. Guess I'll try -50mV now.WJames65 - Friday, March 20, 2015 - link
I bought a barebones Clevo P770ZM equipped with a 980M and added a 4790K. The 4790K seems pretty receptive to undervolting based upon my experiences and experiences of many others as posted in the TechInferno forums. Some people have managed to get as high as 5 GHz with 4.7 GHz more typical. However, for such high speeds, the fans must be run on max, which is accomplished with the hotkey FN + 1. I also suspect those higher speeds may require a delid *shrug*. While I personally wouldn't run a desktop processor in a laptop with those overclocks, it is possible.JarredWalton - Friday, March 20, 2015 - link
Are you saying people are hitting 4.7GHz under a stress test? Because I can get the system to boot at 4.6/4.7GHz but as soon as I start stress testing it's a no go. Trying for -50mV on the CPU now as -100mV didn't work out.ajc9988 - Friday, March 20, 2015 - link
So, take it as you will:I recommend starting with -25mV at a time. First, lock the cache ratio multiplier to 40 (hereinafter stock multiplier). Start at -30 to -50mV under on the cache ratio (note - leave all adaptive voltages set to adaptive and default. If you try setting the adaptive voltage like a desktop, then set an offset on top of it, some weird readings can be had in programs like HWmonitor for both the ring voltage and the IA voltage offset. As I haven't figured this out yet, I'd recommend staying away from it until later if you want to play). Then reduce the voltage from that amount by 25mV until no longer stable in XTU stress test. Then bring it up by 5mV intervals until stable for the test of your choice. What you may want to explore is other tests utilizing the AVX2 instruction set as this is the cause of the extreme heat on Haswell with the newer prime95. Alternatives for lower heat tests are prime95 version 26.6. If you want AVX ( but not AVX2) you can use prime95 27.7 or 27.9. These give you prime95 stability without the insane heat for the platform. Alternatively, loop x264 for testing the AVX set. Either way, the idea is to have the laptop under normal stress situations, not insane heat situations unless you do certain encoding that requires it. Then it is necessary. You just want fully stable. After you find the stable cache ratio, repeat for the core clocks. Lock the multiplier for all cores to be the same and start offsetting. (note - if the C states are enabled, dynamic voltage offset must be true for every possible C-state voltage request. Think of it like a totem pole with set notches in it. These notches correlate to stock voltages for every C-state, including C0 (load). The offset is like cutting that much voltage off the bottom of the totem pole. This means instability may arise entering or coming out of C-states. Just be aware of it). Once you have the Core and Cache offset stable to your liking, then test away with what you like. Benchmark, do your every day tasks, etc. Be aware, it may pass any number of stress tests and still have slight instability. Just increase the Core voltage and keep going. As long as you are under 4.4 ghz, you shouldn't have a need to change the cache voltage for stability (in my experience with my machine, yours may differ). I run everyday at undervolt -65mV Core, -110 Cache (0.995 Vcore) at 40 multiplier all cores and stock cache multiplier. That is low 70s auto fan for XTU and WPrime testing. After I get my pads here, gelid gc-03 extreme, and CLU, I intend on delidding and going beyond (the 4.9GHz was on a delidded CPU). 4.2 should be easy on max fans also in the 70s on lighter stress testing (meaning other than prime95 v.28 or OCCT 4.4.1).
nunomoreira10 - Saturday, March 21, 2015 - link
Did you manage to undervolt? any positive results?ajc9988 - Saturday, March 21, 2015 - link
Also, first try to get 4.5 stable in lower stress test conditions first, then see if the thermal room will allow for 4.6 or 4.7. Unless you won the Haswell chip lottery, 4.6 and 4.7 without delidding will not likely be possible, but up to 4.5 should be if you don't mind seeing temps in the 90s. I am delidding solely to get 4.4-4.5 under autofan in the 70s. I, personally, apply two different settings: work mode and play mode. Work mode is autofan and temps in the 70s. This leaves plenty of thermal headroom and allows for it to be quieter in public, etc. The other is game mode. This is 70s to low 80s at more stress than I do for work mode. It is important to remember that this is a desktop chip with a Tcase of 74.4 degrees Celsius. Laptops are extremely closed cases, meaning that the heat around is nearly what the CPU temp is, meaning 80 should be your upper max for everyday operation (or at least is how I treat my chip for longevity). You will find different offsets on Dynamic Voltage Offset (Vcore offset) depending on the multiplier used. This is because Intel guarantees all chips will function (up to max turbo 4.4GHz) at the stock voltage applied for each multiplier. Each chip is unique and some can use less voltage at a specified multiplier. So the offset will vary for the Vcore depending on the multiplier.Also, there are three types of overclocking: Static, Adaptive, and Dynamic Mode Overclocking. Dynamic Mode Overclocking is what is commonly applied to laptops. This allows for lower voltages while allowing for programs to request more than what the offset normally applies for voltage without crashing the system. Benefit - lower overall voltage (meaning lower heat). Drawback - stability testing sucks, C-states are affected by the voltage offset. Static - applies a set voltage all the time. Benefit - stable under any draw. Drawback - Voltage applied all the time which increases overall heat, requires much higher voltages than any other method of overclocking. Adaptive Overclock - Adjusts only the turbo voltage requests on the CPU. Benefits - Does not affect the voltage of C-states, it only affects the Turbo Voltage (acts as a separate VID state above all C states); allows CPU to request voltages beyond the max turbo voltage set by user. Drawbacks - allows CPU to request voltages beyond the max turbo voltage set by user which causes extreme power draws when running synthetic benchmarks like Prime95, OCCT, etc. Because of these, Dynamic Mode Overclocking is the preferred method of overclocking on laptops. But see: http://forum.notebookreview.com/threads/guide-to-h... . I have not been able to replicate his findings/results with adaptive overclocking while performing Dynamic Mode Offset. Further, I run my CPU under stress at a dynamic offset causing the Vcore to be .0.995V, whereas with setting the Adaptive voltage to .950 Vcore, it still supplies 1.055V Vcore under stress conditions (as with the heat that comes with it). This may be different once the voltage required is greater than Intel's stock voltage at a set multiplier, but for voltages used before that point, it would seem that Dynamic Mode Overclocking provides the lowest voltage to the CPU, and thereby provides the lowest possible heat for the 4790K without advanced cooling solutions (delidding, etc.) for this device.
extide - Saturday, March 21, 2015 - link
Yeah those guys seeing 4.6+Ghz on the laptops, are definitely no stable under prime95 and such.ajc9988 - Sunday, March 22, 2015 - link
Not true. 4.6 and 4.7 was prime95 v.28.5 stable. See http://forum.notebookreview.com/threads/official-c...Now, this immediate testing was XTU, but prime testing did happen (see page 255). Superkyle1721 continued his delidded OC journey to page 258. I, personally, have prime tested and had my web surfing (I'm a tab whore) BSOD my system on Prime stable. This means prime stable isn't the be all end all when firefox brings prime stable to it's knees (over 300 tabs at a time is normal). So go on with prime, it is hot and doesn't guarantee stability for my use. I look at prime95 27.7/27.9 for my AVX testing (10 degrees hotter than others rather than 20 tested by AVX2 instruction set found in prime95 v.28.5 and OCCT4.4.1.) as well as x264 loop. I start with XTU because it is about the easiest to pass. Then move onto Wprime and BurnIn Test (Passmark). After it is stable in these, I do an x264 loop. Then I do either prime95 26.6 (no AVX) or prime95 27.7/27.9 (if testing AVX and not AVX2). Then I do massive blend testing. Heat is not what tells me I'm stable because a pass in prime still fails my browsing habits, needless to say more of my visualizations. It is a great tool at pointing out instability - I admit it is one of the best. But choosing something that is one of the best at what it does that has been made impracticable by heat considerations is ludicrous! If you want a full list of my stress testing programs and benchmark programs, I can get that to you. But Prime95, due to its heat with AVX2, has made itself impractical for most uses and few people do activities that push their processor to those limits. So the average overclocker is building in a 20 degree headroom on his/her system that he/she will never take advantage of. Does that make sense? NO, IT DOES NOT!!! Some people encode, run multiple virtual machines simultaneously, etc. and push their processors to the max on temp reaching the same as Prime95 small FFT. Those people have a need for this to set their thermal limits of their systems to their liking. But for the rest, you set prime95 small FFT to 80 and never see the processor break 65 under load. Why? It is time to start rethinking the Prime or nothing standard. Yes, testing with multiple stress tests to assure stability takes longer. But you can set the temps according to your usage, not some theoretical max that you never push in your use of your machine. Believe it or not, I have had 4.2GHz prime95 stable small FFT with thermal throttle to 4.15 with bad heatsink contact on one of four corners with MX-4. I have had it 4.5 stablish with thermal throttle to 4.42 with XTU and WPrime (I will not prime test if weaker tests thermal throttle, that is ridiculous to consider and you should have your head examined if you think otherwise). Superkyle1721 had, after delidded, got 4.4 prime95 for 20min. large FFT with temps never above 92 degrees. Granted not as hot as small FFT, but still a fair score. So please read and research before saying those guys are not prime stable as if that is the only stability that matters. Open your mind to new possibilities please.
scook9 - Friday, March 20, 2015 - link
The problem with desktop CPUs in a laptop is that the cooling is WAY less efficient due to the use of a heatspreader. Laptop CPUs have the exposed die with no heatspreader in the way so you have a much shorter and more efficient path for heat to flow and cooling to be effective. Combine that with the fact that the laptop CPUs are binned for much higher efficiency than desktop parts and it starts to explain why laptop CPUs make more sense in laptops :) They do cost more as a result, but pretty much since Sandy Bridge, there has been very little reason to bother with desktop parts in laptops, clock for clock the performance is identical.An Intel Core i7 4810MQ can turbo up to 3.8 GHz vs 4 GHz for a 4790 or 4.4 Ghz for the 4790k. At the same time power usage is HALF resulting in much better thermals and more reliable performance as well as gaining the benefit of technologies like Optimus. If you are really that hell bent on CPU performance for gaming in a laptop than money is clearly not a limiting factor so get the 4940MX can clock it well past the stock clocks of a 4790k (this is very doable). At this class of laptop the premium for the extreme CPU is not as bad as it sounds, adding $800 to a $3000 laptop is doable for the people buying $3000 laptops usually. I have played that game in the past, getting the extreme CPU and overclocking the hell out of it in a top tier gaming laptop and after getting benchmarking out of my system (which took about 3 years) I now usually go for the entry level quadcore to have all the threads I want and not pay out the nose for marginally higher clocks.
What I was able to pull off back in 2011 (with ambient room temp cooling - some guys were doing phase change and dry ice):
http://forum.notebookreview.com/threads/official-a...
Got that CPU up to 4.5 GHz pretty reliably on all 4 cores with no throttling.
scook9 - Friday, March 20, 2015 - link
I also was able to push the hell out of the older Core 2 Quad era stuff too:http://forum.notebookreview.com/attachments/3dmark...
http://forum.notebookreview.com/attachments/3dmark...
But that DID require putting my laptop in a chest freezer to cool the CPU - 1.5V ran pretty hot. At the end of the day though, the crappy nvidia chipset in the original M17x was my limiting factor with my Ram and not the CPU.
CrazyElf - Friday, March 20, 2015 - link
To be honest, laptops probably don't have the margins for overclocking that a desktop would.For the desktop CPU, it is already pretty hot to begin with. You might be able to knock 15-20C down by delidding that 4790k, much like a desktop. The problem is, with a desktop you can use a giant cooler like the Noctua D15, or water cool. You cannot with a laptop.
GPUs have similar problems. Large triple slot coolers and water blocks are available - indeed they are made specifically for desktop overclocking. There's no way to do that in a laptop. It just isn't possible.
Khenglish - Friday, March 20, 2015 - link
Did you see the GPU temps? With a 20% overclock it only reached around 77C, which is cooler than many stock coolers on similar desktop cards.CPU temps are bad though. I think the problem is that clevo went with a combined GPU/CPU heatsink for this laptop, which is something they have not done before. While this sounds good at first, it makes having good die contact on both CPU and GPU nearly impossible without a large amount of flex in the heatsink, which the P750ZM heatsink does not have.
CrazyElf - Friday, March 20, 2015 - link
Apples to oranges. Maxwell is a pretty cool running chip on desktops too. If you are comparing the 980M to the AMD 290X, then yes, the desktop chips are hot in comparison. But remember, we should be comparing the 980M to a desktop Maxwell, and this is a chip that has 1/4 of the units stripped (so 1536 out of 2048 active) compared to the desktop part, which is already pretty cool running.A delid as I said might solve the problem partly like in desktops of the 4790k, but either way, there isn't much OC headroom in that chip even with the delid.
To be honest, the GT72 is a better choice IMO:
http://www.anandtech.com/show/8694/msi-gt72-domina...
The CPU runs cooler and the battery life is better, should you ever need it. It is somewhat slower, but not by much. Plus newer versions with an IPS screen are available - I just wish Anandtech had reviewed it with the IPS screen.
I just wish that instead of overclocking, that a full 2048 version of the 980 were available, running at a lower clockspeed. My wet dream would be the big 3072-Titan X die severely underclocked on a laptop, but that would never happen for various reasons.
Khenglish - Saturday, March 21, 2015 - link
Yeah full 2048 would rock. I am 100% convinced that the only reason it just has 1536 running is so Nvidia can release a fully enabled chip in the future and say they have a new, faster card.JlHADJOE - Saturday, March 21, 2015 - link
Actually, looking at the combined CPU and GPU temps, it's pretty obvious that system is more or less maxed out thermally.The CPU is pegged at 95-99C, and the GPU is similarly pegged at 77C. When the GPU clock is raised is that the CPU clock goes down, so "overclocking" here merely trades CPU clocks for GPU.
Not that it's a bad idea really, as shown by the game benchmarks, but it does show that there is close to no headroom at all in the Clevo's combined thermals.
Hrel - Friday, March 20, 2015 - link
I think overclocking with today's hardware is stupid, I have no interest in it. I tend to agree with Nvidia on OC.However, that doesn't mean they should go so far as to BLOCK people from being able to do it. Ultimately once they've bought it, it's their choice. At least it should be.
Have OC void the warranty and be done with it. There's no reason to do anything more than that. "You wanna overclock? Fine, do so at your own peril. We wash our hands of you".
This attitude would bring their position from being the right one for 99.9% of the market to 100%.
will54 - Friday, March 20, 2015 - link
I thought they already voided the warranty on OC's or is it just when you go with a modded vbios that they void the warranty ?Buk Lau - Friday, March 20, 2015 - link
Nice work Jarred, glad to see authoritative sites like AT starts to acknowledge OC on mobile GPU! Although you still didn't test with USB 3.1 ports on this machine (so you didn't have peripherals available?)... and in the future I would recommend when you are doing stress tests, just run Prime95 and and Furmark instead for maximum heat on the system. Running Prime95 and tombraider at the same time actually reduces CPU load, because floating point calculation requires much higher work load than game physics. That aside you did a fantastic job! Funny when you noted on potential reasons why Nvidia blocked OC, every generation some cards are just rebrands of old cards with a slightly higher clockspeed. So essentially you can get a free upgrade yourself when you do that, and OC damaging the gpu might not as much of a threat if Nvidia is doing it themselves every generation LOLajc9988 - Friday, March 20, 2015 - link
I disagree with your choice of tests. Max heat isn't the goal with a laptop UNLESS YOU LITERALLY PUSH THE HEAT ON YOUR MACHINE DAILY FOR ITS INTENDED PURPOSE. I had to change the way I thought about overclocking when I came to a laptop. It isn't about max heat like desktop testing (which now reflecting on it is a little stupid if you never do real world activities that push it like that). You want to test max heat for real world type tests. Anything you may do (x264 for avx encoding, etc. There is a long list of stress tests that fully stress the machine without giving synthetic instruction sets to push the hardware to a heat max.). Also, Furmark and Kombuster are vbios blocked in the premamod bios.JlHADJOE - Saturday, March 21, 2015 - link
Yipes! Close to 100°C on the CPU. That is insane.They should run heatpipes to a round metal plate where you can set a mug somewhere on that thing. Cools the CPU, and keeps your drink warm!
zodiacfml - Saturday, March 21, 2015 - link
Nah, this is no way advisable as longevity and reliability will be sacrificed. It's rare that notebook cooling have been over engineered and mobile GPUs are notorious for deteriorating solder joints which can't be permanently fixed cheaply.smilingcrow - Saturday, March 21, 2015 - link
"Assuming 85% efficiency on the power bricks the 230W AC adapter would be very close to 100% load."I imagine you mean that it's rated for 230W DC output otherwise it would be out of spec as in testing you hit 265W AC. That's ~225W DC output.
waldojim42 - Tuesday, March 24, 2015 - link
I seem to be missing something, who gets power supplies rated based on input wattage, and not output? EVERY laptop power supply I own is rated on the power supplied to the machine. It makes no sense to me to rate the input.radeonex - Saturday, April 11, 2015 - link
I noticed that in this article, for the stock configuration, the GPU temp for the P750ZM stayed below 70 C roughly. However in the full review of the P750ZM, the GPU temp that was shown hovered around 75 C. Can you please comment on the discrepancy?