Introduction

Back in November 2000, when Intel announced the release of the Pentium 4 1.4GHz and 1.5GHz CPUs, its high price and disappointing performance drove people away from buying the Pentium 4 for their systems.  The performance was barely on par with the Pentium III 1GHz and slower than the 1.2GHz AMD Athlon in most benchmarks, not to mention the fact that they were associated with a $1000 price tag.

Just last week Intel announced their new 1.7GHz Pentium 4 , which has put the Pentium 4 back near the top of the benchmarks.  As with any other new CPU launch, the price drops are not far behind, and the Pentium 4 is no exception. With the latest round of price cuts, the Pentium 4 is now much more reasonably priced. Of course, price drops on RDRAM and i850 motherboards have been happening gradually over the past few months as well

Ever since the debut of Pentium 4 we haven’t really looked at any individual motherboards using the i850 chipset, mainly because it seemed that nobody wanted a Pentium 4 in their system.  However, with the aforementioned price drops and the introduction of higher clocked chips, that’s all changing. That means it’'s time for us to start looking at what different manufacturers have to offer on the motherboard side of things. 

To kick off our series of i850 motherboard reviews, nothing could be better than a board from ASUS, the largest motherboard manufacturer in the world whose performance and reliability is well known within our community.  Their reputation is based on the numerous high quality and high performance motherboards they have produced, such as the A7V133 and the CUSL2.  Their products are welcomed by both OEM builders for their rock solid stability and by hardware enthusiasts for their overclocking ability.  Entering the Pentium 4 era, ASUS once again has their own unique solution, one that should live up to their reputation.

They called it, the P4T.

In the past, when processors ran at relatively low FSB speeds, in the 66 to 100MHz range, signaling was not a serious issue.  So most of our focus regarding the layout of a board was on the placements of components and how that affected airflow and usability.. 

However, that all started to change with the advent of the 133MHz FSB speed, not to mention the recent AMD EV6 bus, DDR and Rambus technology.  With these new technologies having a much higher data rate, signaling has become a much more important issue for a motherboard designer.  Length of traces, coupling between traces and components, noise, etc. all come into play and affect the stability of the systems.  We have seen quite a few examples of the limitations of these designs, such as the Intel i815E chipset not being able to run more than four banks of memory at 133MHz, the Intel i820 chipset not reliably supporting more than 2 RIMM slots, and the majority of DDR motherboards only having two DDR DIMM slots (although with the proper design it is possible to have up to 4 DDR DIMM slots).

Proper signaling is best achieved by careful layout of the PCB.  From our experience, ASUS has always put a lot of effort into truly understanding the chipset and constructing their own unique layout of the boards rather than just going with a variation on the reference design provided by the chipset manufacturer.  One good example is the A7V and A7V133, which have a vertically mounted PCB with the voltage regulator.  Even our recently reviewed CUV266 has a very different layout from anything else we have seen.

Click to Enlarge

With the P4T, ASUS once again shows us that they took quite a bit of effort in redesigning the board, since the layout of the board is very different from the reference design.  For starters, the 82850 Memory Controller Hub (MCH) is located close to the front of the board with the CPU socket is behind the MCH. 

The most interesting part of the design lies in the RIMM slots, which are mounted parallel to the right side of the board, much like the DIMM slots of the CUV266.  This design results in shorter traces, resulting in superior performance and stability. 

ASUS even changed the arrangement of the RIMM slots to help boosting performance.  Remember that the i850 chipset requires you ato install RIMMs in pairs, meaning that if you want to have 128MB memory you will need two 64MB RIMMs (which is exactly what Intel bundles with retail Pentium 4s).  In most Pentium 4 boards, even Intel’s own reference design, the two RIMMs are installed together, and the other slots are filled with Continuity RIMM (CRIMM).  However, with the P4T, you actually alternate the RIMM and the CRIMM modules.  Fortunately, this is clearly documented in the manual.

The RIMM configuration used in majority of Pentium 4 boards.

The RIMM configuration used on the P4T.

The main power supply connector is nicely placed at the front right corner, which would be relatively close to the power supply, while also preventing you from running the power cable over the CPU or memory.  An “AUX” power supply connector, similar to those used on old AT  form factor boards, is located beside the regular power supply connector. 

The IDE and floppy controllers are located in front of the 82850 MCH so they will not block any of the expansion slots.  Since the RIMM slots are now placed along the right side of the board, you don’t have to worry about not being able to install memory after installing the video card, a minor problem we see all too often.

More of that ASUS flair

Unfortunately, the placement of the USB ports at the back of the P4T really puzzles us.  As you can see, the two USB ports are not placed next to the mouse / keyboard connectors.  Rather, the serial / parallel ports are shifted towards the PS/2 connectors, and the USB ports are placed at the other end of the I/O panel. We have seen this configuration a few times before, and its always been on server boards - perhaps ASUS’ intended target market. Regardless, this means that you will need a special I/O shield for the P4T. Our test sample did not include such a shield, but our experience with ASUS tells us that the shipping version probably will include it. 

The I/O panel of the P4T.  Notice that the USB ports are not beside the PS/2 connectors.

Instead the USB ports are moved to the other end of the I/O panel.

Don’t forget that the i850 chipset also requires an ATX12V power supply to function properly.  On the P4T, the ATX12V connector is located next to the IDE connectors, which is pretty close to the other two power supply connectors to make sure that all the cables are localized together. 

The original ATX power supply connector and the AUX power connector.

The new ATX12V 2 x 2 connector.

The second part of the ATX 2.03 specification calls for four extra mounting holes around the CPU socketso support a heatsink retention mechanism.  That means you’ll need a new case to go along with your new motherboard. 

Fortunately, ASUS has a solution for those that don’t want to go out and buy a new case. When you open up the P4T’s box, you will notice that an additional metal plate, a piece of rubber pad, and a couple of mounting devices.  ASUS calls this plate the metal baseboard, and you basically put the rubber pad on the baseboard, then put the motherboard on top and screw the board onto the plate. The plate provides the mounts for the heatsink retention mechanism and mounts to your current ATX case.

The plastic pad and the baseboard bundled with the P4T.

The set of screws and retention modules bundled with the P4T.

Now you can easily mount the baseboard, which looks identical to the normal ATX format, to the case, so you can fit your Pentium 4 system in your old case.

After installing the board on the baseboard, the board is physically around 0.5cm above the baseboard.

New Chipset, Old Brother

As we have mentioned in our initial Pentium 4 review, the i850 chipset is actually very similar to the i840 chipset with some changes.  The i850 chipset supports the new Pentium 4 AGTL+ bus and its quad pumped 100MHz FSB, effectively running at 400MHz. 

Unfortunately, the 82850 MCH only supports 1.5V signaling, so the AGP Pro slot on the P4T is keyed for 1.5V AGP devices only. For the most part, this will only exclude many AGP 2X cards and a few AGP 4X cards, the most notable of which is the 3dfx Voodoo5 line. 

82850 MCH

There are a total of four RIMM slots on the PT4, and that will be the case for all current Pentium 4 motherboards.  You will have to follow the instructions outlined in the manual to insert RIMMs and CRIMMs in the correct configurations.  Each RIMM slot can accept 64MB, 128MB, or 256MB modules, meaning that the maximum support memory configuration is 1GB of RDRAM.

Like the i815E chipset, the i850 chipset uses the 82801BA I/O Controller Hub 2 (ICH2) for all PCI devices and I/O controls.  The ICH2 supports two Ultra ATA 100 channels and two USB root hubs for a total of four USB ports.  Two of the four ports are located on the I/O panel at the back of the board, and the connector for the third and fourth ports is located on the left side of the board.  ASUS has included the necessary bracket, which contains two USB ports and all the cables, so you can take advantage of the two extra ports right out of the box.

82801BA ICH2

The 5/1/0/0 (PCI/AGP/CNR/ISA) expansion slot configuration is pretty much the standard these days.  The five PCI slots should be enough for most users, although we have seen some boards offer six PCI slots for more flexibility.  The most interesting thing is that ASUS, being the largest OEM supplier in the world, did not include a CNR slot as the default setup, which could help OEM builders provide cheap network solutions. Their decision was probably due to the fact that CNR devices are not widely available on the open market at all.  Nevertheless, ASUS still states that there is an option to take advantage of the ICH2’s integrated LAN controller, and the Ethernet RJ-45 port would be placed on top of the two USB ports within the I/O panel.

Yet another surprising decision by ASUS is the omission of an on-board audio setup, which is another thing most OEM builders take advantage of to help reduce costs. 

Our theory on all this is that ASUS has realized that the majority of hardware enthusiasts building systems for themselves do not take advantage of host-based AC’97 audio, preferring to use their own sound cards instead. The same goes with CNR. As such, ASUS has decided to make these options available to OEM’s to keep them happy, while at the same time not passing on their costs to the enthusiasts that won’t use them anyway. Kudos to ASUS for such a wise decision.

Silkscreen for optional AC’97 CODEC

Overclocking: Staying at the Top

Despites the fact that ASUS is a major OEM supplier, their products are also welcomed by the majority of the hardware community for their strong overclocking abilities and rock solid performance.  ASUS clearly wanted to do it once and for all with the P4T, making it one of the best Pentium 4 boards in the market.  And throughout our thorough testing, we noticed that ASUS covered almost every category we could come up with.

The P4T features a fully jumperless configuration so you can perform almost all overclocking right inside the BIOS.  At the same time, ASUS also keeps a set of dipswitches for you to perform overclocking on the board as well.  While this is definitely not as easy as jumperless setup, the dipswitches are very useful for OEM builders who want to prevent customers from changing  BIOS settings incorrectly.

Even though the P4T allows you to change your multiplier ratio inside the BIOS or using the dipswitches, it only works on Intel’s internal engineering samples that are multiplier unlocked. All CPU’s available on the market should be completely multiplier locked. Fortunately, FSB overclocking is still a good way to overclock, and ASUS has done a very good job in that area as well.  Within the BIOS, you can easily select FSB speeds between 100 / 103 / 105 / 108 / 110 / 112 / 115 / 118 / 120 / 122 / 125 / 130 / 133MHz.  That’s a decent selection, but we’d still like to see FSB speeds adjustable in 1MHz increments.

The set of dipswitches on the P4T.

Unfortunately, ASUS was not able to implement all the possible FSB speeds inside the BIOS, and so for speeds from 133MHz to 156MHz you will have to go to the dipswitches.  Using the dipswitches the extra FSB speeds available are 136 / 138 / 140 / 142 / 144 / 145 / 148 / 150 / 152 / 154 / 156 MHz.  When you select FSB speeds inside the BIOS, the corresponding PCI and AGP bus speed are set automatically to be as close to the spec as possible, but with the dipswitches you can actually have several selections for PCI and AGP speeds with the same FSB speed setting.

ASUS also provides some CPU core voltage settings inside the BIOS - from 1.700 to 1.850V in 0.025V increments, which should be sufficient for most overclocking endeavors.  Unfortunately, I/O voltage tweakings are not available on the P4T, something that has proven to help maintain stability of the system under extreme overclocked situations.

With most RDRAM setups memory tweaks are not as common as what we would find on boards using SDRAM simply because the timing is more tightly controlled.  Luckily, ASUS does offer a one setting to tweak RDRAM timing when you overclock the FSB speed.  This setting allows you to control the ratio that the RDRAM runs at, either 3x or 4x.  Specifically, with a default FSB of 100MHz, 3x allows you to run your RDRAM at PC600 and 4x allows you to run the RDRAM at PC800, which are exactly the two RDRAM standards commonly available today. (Don’t forget that RDRAM also operates in a DDR fashion, hence the 4x setting results in PC800 operation with a 100MHz FSB).   

Unfortunately since most PC800 RDRAM modules are not stable at speeds higher than 900MHz, ramping up the FSB speed without reducing the memory ratio could limit the overclocking potential severely.  At 133MHz FSB with a 4x memory ratio, your RDRAM will effectively be running at 1066MHz, which is not entirely practical.  However, if you drop your ratio to 3x, and you will be back at 800MHz, which is right on the spec.  Using the same philosophy, ramping the FSB speed to 150MHz with a 3x memory ratio, your memory clock will effectively be 900MHz, which is still marginally acceptable provided that you have high quality modules.

Like the Intel reference board, ASUS has included a heatsink on the 82850 MCH, with a new mounting mechanism to make sure the MCH is running at an acceptable temperature range.  The size of the heatsink is considerably larger than those used on chipsets in the past, but is typical of what we’ve seen on other i850 boards.  ASUS has also decided to once again use their own ASIC chip for hardware monitoring, which provides readings for three temperatures and three fan speeds from within the BIOS.  There is a connector on the motherboard for an external thermistor that can measure any temperature in the system, but ASUS did not include an actual thermistor with our evaluation sample.

The ASUS ASIC for hardware monitoring

The heatsink on the 82850 MCH

The new mounting mechanism allows you to remove the heatsink easily

Our overclocking tests on the P4T show that the board is truly a phenomenal one.  By lowering the memory ratio to 3x and lowering the multiplier ratio settings of our engineering sample chip to avoid the memory and CPU being the bottleneck, we were able to push the FSB speed to a surprising 145MHz without losing any stability.  This is 45% overclocking and we were very pleased with it. Since the Pentium 4’s bus is “quad pumped,” we are effectively running at a FSB of 580MHz.

Pros and Cons

Stability has always been a hallmark of ASUS products, and the P4T was no exception as it was one of the most stable motherboards we have ever tested.  With four 1200uF capacitors and seventeen 1500uF capacitors located around the RIMM slots, 82850 MCH, and the CPU socket, combined with the unique board design, the P4T refused to crash once after 48 hours of stress testing.  Even under our overclocking tests, the board would not crash.

Remember the new ATX 2.03 specification Intel announced together with the Pentium 4?  A lot of people complained about the specifications since they would have to purchase not only a new case, but  also a new power supply with the ATX12V connector.

As mentioned previously, ASUS gets around the case problem by having their own baseboard design, but they have also put in quite a bit of effort to get around the new power supply specification as well.  As an experiment, we unplugged both the ATX12V and AUX power connectors, leaving only the standard ATX connector in place. We then proceeded to run our normal stress tests and found that the P4T still did not crash once within 16 hours, showing that the board was able to draw all the necessary current solely from the ATX power connector.

This discovery shows that there is a good chance that you do not in fact need to go out and get a new power supply with the ATX12V connector.  Of course, this is also partially dependant on the quality of your current PSU. 

The biggest complaint we have with the P4T, if any, is the lack of the now common IDE RAID support.  ASUS has been using a Promise IDE RAID controller on several of their other motherboards, but they chose not do so with the P4T.  It’s not even an optional feature, so ASUS will have to redesign the PCB if they want to implement one in the future.

ASUS has always had excellent manuals for end users, and that trend continues with the P4T.  It contains very detailed instructions and diagrams on how to install the motherboard, RDRAM, and the CPU, information on all the connectors, jumpers, and dipswitches settings, as well as a detailed explanation of all the BIOS settings.  Moreover, ASUS also included sections on how to install all kinds of drivers and utilities that come on the bundled CD. 

The Test

In recent times, choosing a motherboard cannot be completely determined by a Winstone score. Now, many boards come within one Winstone point of each other and therefore the need to benchmark boards against each other falls. Therefore you should not base your decision entirely on the benchmarks you see here, but also on the technical features and advantages of this particular board, seeing as that will probably make the greatest difference in your overall experience.

Test Configuration
Processor(s):	Intel Pentium 4 1.4GHz OEM
RAM:	2 x 128MB Mushkin PC800 RDRAM
Hard Drive(s):	Western Digital 153BA Ultra ATA 66 7200 RPM
Bus Master Drivers:	Intel Ultra ATA 6.10
Video Card(s):	NVIDIA GeForce 2 GTS 32MB DDR
Video Drivers:	NVIDIA Detonator 6.50
Operating System(s):	Windows 2000 Professional
Motherboard Revision:	ASUS P4T Revision 1.06
BIOS Revision:	1001

 

Windows 2000 Performance
	SYSMark 2000	Content Creation Winstone 2001	Quake III Arena (640x480x16)
ASUS P4T	204	52.4	191.6
Intel D850GB	204	53.6	192.5

The P4T performs pretty much on par with the Intel reference board. The SYSMark 2000 and Quake III Arena scores are virtually the same. In Content Creation Winstone 2001, the P4T came up a more or less insignificant 2% short.

Final Words

We’ve seen ASUS set the standard for a particular type of motherboard in the past and we do believe they have done it again. While companies like ABIT are jumping onto the Pentium 4 bandwagon now, ASUS has proven to have one of the best Pentium 4 out there. The only downside, if any, would be the lack of an on-board IDE RAID controller.

Fortunately, that’s a minor complaint since everything else is close to perfect on the P4T. ASUS’s unique board design once again proves to be very effective in providing solid performance and stability, which performs better than the reference design in some cases and runs smoothly without a crash in all our stress tests.

The overclocking package on the P4T is quite good as well, giving you a lot of flexibility in fine tuning your system to squeeze out the last drop of performance from the system. Even under heavy overclocking situations, the P4T ran reliably without a crash.

Quite possibly one of the most compelling features of the P4T is its ability to work in a standard ATX case with a standard ATX power supply thanks to the baseboard included in the box and the careful design of the board to run properly with standard ATX power.

All in all, the P4T is yet another impressive motherboard from ASUS, whether you want to push your system to the max or you just want to be crash free.

How it Rates

AnandTech Motherboard Rating
	Rating (x/10)
Performance: The P4T performs on par with the Intel reference design	6.0
Price: ASUS boards are generally priced above average, but surprisingly the P4T is not among the most expensive i850 boards out there. It’s still a little bit above average, but it’s worth it for what you get	6.0
Stability The stability of the P4T is simply amazing. All the way from the initial installation until we finished all the benchmarks and stability tests, the board never crashed, not even once. It didn’t crash under non-overclocked situations for 48 hours, not under extreme overclocked situations, and not even if we unplugged the ATX12V and AUX power supply connectors.	9.5
Features The full overclocking package provides you the option to fine tune your system. The only complaint we have is the lack of an on-board IDE RAID controller - something that can always be added via a PCI card.	7.5
Layout ASUS again came up with their own unique layout design, which proves again to be effective in boosting the performance and stability of the system. In general the layout of the board is very nice, with our only complaint being the non-standard layout of the ATX I/O panel.	6.5
Availability Being the largest manufacturer of motherboards in the world offers the major advantage of being very easy to find. They are widely available in local computer stores, including stores like Micro Center and Fry’s. Of course, purchasing ASUS products online is just as easy.	8.5
Documentation & Software Bundle The manual is again very nicely written with just about every piece of information you might need for the board.	8.5
Overall Rating - not an average Click here to find out why	8.5