I've seen the graphic shown on the bottom half of that display a number of times when talking about signalling quality for new memory busses. I've never seen a good explanation of what it's supposed to be showing other than at a very high level that sharp skinny lines are good and fat smeary ones are bad.
The simplest explanation: What you essentially want from this diagram is figure out if you have reliable bit value of 1 or 0. So, you keep switching between the two and measuring voltage to see if you can distinguish the two. If your eye is wide open, you have a reasonably large window (both time and voltage) in which you can measure to know if you have a 0 or 1. If you have smeary mess of an eye that is barely open, your time window and voltage window is smaller. It will still work in a lab, but fail once you throw in real-world mess of temperature, component degradation, supply voltage/ripple or whatever else might influence the device.
Now, the eye diagram also tells where you screwed up and other reliability considerations, eg eye might be smeary because your rise from 0 to 1 isn't always as fast; or it might be smeary because rise doesn't always start at the same instant; or it might be nicely open but show sizeable voltage overshoots which might damage other components over time. From these features, you can figure out what you need to improve.
I’ve played with the M8020 at the lab I work at. It has an ATX power connector, mini USB port, an ethernet port, and a few dozen SMA connectors. That’s it. The only way to control it is through the mini USB. You can’t run the remote control software over ethernet. If one crappy port breaks you have a mllion dollar brick.
It’s really bizarre to see T&M news coverage on a tech site. Judging from the comments it doesn’t feel like it belongs here. Were you guys at designcon?
It's not unwelcome though. Knowing the state of DDR5 testing gives us a teaser on how development is going. I suppose 2020 is to much to hope for though.
Hey we will never need more than 640K oh wait that's not right. Yes for sure good to see DDR5 may move forward and at some point actually come to the market. The only thing that sucks is I am planning on upgrading to one of those shiny new Ryzens in June-July time frame and they only support DDR4. So if I upgrade now then a year later DDR5 releases I will feel like I do now with my DDR3@2400MHz slow and using outdated tech....:) But hey I guess if I get fast enough DDR4 it won't matter to much anyway.
It will probably take another year before you can get modules decisively faster while running at reasonable voltage. Getting new Ryzen in 4-5 months with DDR4s should not disappoint you at all.
"It's not unwelcome though. Knowing the state of DDR5 testing gives us a teaser on how development is going. "
Bingo.
It's not as if I expect any AnandTech readers to buy the system (though we do have a lot of industry readers, funny enough). However it's a useful proxy for keeping an eye on DDR5 development, especially as there aren't going to be any "big" announcements this soon.
We've seen a handful of other posts about the first DDR5 dram chips and first stand alone DDR5 memory controllers over the last year or two. I don't see anything out of line from that in also reporting the first test machine.
It’s a suite of machines and they test a lot more than just DDR5. Keysight is also not first to market for DDR5 test solutions. I’m sure there’s is very good and is priced appropriately. There is always news in this space but it isn’t covered by a site like anandtech because the readers are consumers more than they are engineers. Where are the anandtech articles covering 400GBASE-KR4 development?
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DanNeely - Wednesday, February 6, 2019 - link
I've seen the graphic shown on the bottom half of that display a number of times when talking about signalling quality for new memory busses. I've never seen a good explanation of what it's supposed to be showing other than at a very high level that sharp skinny lines are good and fat smeary ones are bad.brakdoo - Wednesday, February 6, 2019 - link
https://en.wikipedia.org/wiki/Eye_patternZizy - Wednesday, February 6, 2019 - link
The simplest explanation: What you essentially want from this diagram is figure out if you have reliable bit value of 1 or 0. So, you keep switching between the two and measuring voltage to see if you can distinguish the two. If your eye is wide open, you have a reasonably large window (both time and voltage) in which you can measure to know if you have a 0 or 1. If you have smeary mess of an eye that is barely open, your time window and voltage window is smaller. It will still work in a lab, but fail once you throw in real-world mess of temperature, component degradation, supply voltage/ripple or whatever else might influence the device.Now, the eye diagram also tells where you screwed up and other reliability considerations, eg eye might be smeary because your rise from 0 to 1 isn't always as fast; or it might be smeary because rise doesn't always start at the same instant; or it might be nicely open but show sizeable voltage overshoots which might damage other components over time. From these features, you can figure out what you need to improve.
edzieba - Wednesday, February 6, 2019 - link
"M8040A 64 Gbaud High-performance bit error rate tester (BERT)"Somewhere in the bowels of Keysight is an engineer furiously trying to backronym ERNIE to a piece of production test equipment.
close - Wednesday, February 6, 2019 - link
Waiting for the inevitable "no USB C or 10Gb Eth, no buy".brakdoo - Wednesday, February 6, 2019 - link
Don't forget the headphone connector or missing certification for waterproofing.close - Wednesday, February 6, 2019 - link
Damn it! I knew there was something else I cannot live without. Also microSD. And 4K 144Hz. And RGB LEDs all around.willis936 - Wednesday, February 6, 2019 - link
I’ve played with the M8020 at the lab I work at. It has an ATX power connector, mini USB port, an ethernet port, and a few dozen SMA connectors. That’s it. The only way to control it is through the mini USB. You can’t run the remote control software over ethernet. If one crappy port breaks you have a mllion dollar brick.DanNeely - Wednesday, February 6, 2019 - link
How else are they supposed to sell the $100k/year service contract.PeachNCream - Wednesday, February 6, 2019 - link
That test rig needs a lot more RGB if Keysight intends to earn any street cred. Maybe a set of alloy rims too...Oh, can it run Crysis?
VivaLaPanda - Wednesday, February 6, 2019 - link
I remember hearing about one of our engineers getting Doom to run on one, but I don't know about Crysis...willis936 - Wednesday, February 6, 2019 - link
It’s really bizarre to see T&M news coverage on a tech site. Judging from the comments it doesn’t feel like it belongs here. Were you guys at designcon?Mr Perfect - Wednesday, February 6, 2019 - link
It's not unwelcome though. Knowing the state of DDR5 testing gives us a teaser on how development is going. I suppose 2020 is to much to hope for though.rocky12345 - Wednesday, February 6, 2019 - link
Hey we will never need more than 640K oh wait that's not right. Yes for sure good to see DDR5 may move forward and at some point actually come to the market. The only thing that sucks is I am planning on upgrading to one of those shiny new Ryzens in June-July time frame and they only support DDR4. So if I upgrade now then a year later DDR5 releases I will feel like I do now with my DDR3@2400MHz slow and using outdated tech....:) But hey I guess if I get fast enough DDR4 it won't matter to much anyway.HollyDOL - Wednesday, February 6, 2019 - link
It will probably take another year before you can get modules decisively faster while running at reasonable voltage. Getting new Ryzen in 4-5 months with DDR4s should not disappoint you at all.rocky12345 - Wednesday, February 6, 2019 - link
I was thinking the same thing after I posted my comment. I am still going to pick up the new CPU & Memory & main board and enjoy my new toys.Ryan Smith - Wednesday, February 6, 2019 - link
"It's not unwelcome though. Knowing the state of DDR5 testing gives us a teaser on how development is going. "Bingo.
It's not as if I expect any AnandTech readers to buy the system (though we do have a lot of industry readers, funny enough). However it's a useful proxy for keeping an eye on DDR5 development, especially as there aren't going to be any "big" announcements this soon.
DanNeely - Wednesday, February 6, 2019 - link
We've seen a handful of other posts about the first DDR5 dram chips and first stand alone DDR5 memory controllers over the last year or two. I don't see anything out of line from that in also reporting the first test machine.willis936 - Wednesday, February 6, 2019 - link
It’s a suite of machines and they test a lot more than just DDR5. Keysight is also not first to market for DDR5 test solutions. I’m sure there’s is very good and is priced appropriately. There is always news in this space but it isn’t covered by a site like anandtech because the readers are consumers more than they are engineers. Where are the anandtech articles covering 400GBASE-KR4 development?VivaLaPanda - Wednesday, February 6, 2019 - link
Yeah, I think this is the first time I've seen our products in wider ranging tech newsGreenReaper - Wednesday, February 6, 2019 - link
Why not request the price, so you can tell it to us? :-pIII-V - Wednesday, February 6, 2019 - link
If I remember correctly, the oscilloscope is over $10 million.III-V - Wednesday, February 6, 2019 - link
Oops, I remembered incorrectly. Drop a zero from that.