ASUS EAH3850 X2: a metal-framed exclusive

Today, we are reviewing the technologies of multi-GPU configurations - AMD CrossFire and NVIDIA SLI. We'll be examining their efficiency to find out which operating system - Windows XP or Windows Vista - is more suitable for their operation. We'll be using the exclusive video card ASUS EAH3850 X2 with a proprietary cooling system, as well as the overclocked ASUS EN9800GX2, plus three more video cards, at least two of which will be interesting to many. We start our introduction to video cards with the most interesting part, the exclusive.

ASUS EAH3850 X2: Layout and Features

ASUS EAH3850 X2 is shipped in an orange-black box like all the other video cards of the Radeon family produced by this manufacturer. Note that the box is quite large, as big as the video card itself.

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Here is the package bundle of the new video card:

• power supply adapter for PCI-Express video cards;
• DVI -> HDMI adapter;
• DVI -> D-Sub adapter;
• S-Video > Component out adapter;
• CrossFire bridge;
• drivers CD;
• CD with a user's manual;
• User's manual;
• Case for CDs;

Engineers at ASUS have used a proprietary cooling system. They managed to create an impressive product - the metal housing accentuates the status of the card, with a couple of fans add more credit to the cooling system.

The reverse side of ASUS EAH3850 X2 is not equipped with additional cooling devices, which may puzzle you. But there is no need to worry - the memory chips on the reverse side won't overheat.

If you are annoyed by the noise from the fans, you can easily fit 1-2 slow 120-mm fans instead. For that, just dismantle the metal housing off the video card by turning out 5 screws.

Each GPU is cooled with its own radiator which at the same time cools the memory chips and components of the power supply subsystem.

The "bare" ASUS EAH3850 X2 looks very similar to Radeon HD3870 X2, but there are some differences between them, e.g. in the power supply subsystem.

The memory chips are made by Qimonda and offer 1 ns access time, which is equivalent to the effective frequency 2000 MHz. But the real operating frequency is lower.

The next participant of today's review also uses two GPUs at the same time. Well, meet the guest.

ASUS EN9800GX2 TOP

Although ASUS EN9800GX2 TOP belongs to the GeForce family, its package is made in grey tints, which is not typical for ASUS. That is because of the game "Company of Heroes" whose full version comes as a bundled item with the new video card. And of course we can't help pointing to the fact that the video card is factory-overclocked, which has given extra 11% performance gain, according to the manufacturer. But no info is as to where and under what conditions that was achieved.

Here is the package bundle of the new video card:

• power supply adapter for PCI-Express video cards;
• PCI-express 2 x 6 pin > 8 pin power supply adapter;
• DVI -> D-Sub adapter;
• a cable to apply S/P-DIF sound signal to the video card inside the computer;
• drivers CD;
• CD with a user's manual;
• CD with the Company of Heroes;
• User's manual;
• Case for CDs;

ASUS EN9800GX2 TOP differs from the "regular" reference video card in overclocking only. Its design is such that you'd better avoid dismantling it because there is a high risk of damaging it. Therefore, we'd rather not dismantle it - for the details of the interior of the video card, read our previous review.

Look at the proprietary sticker. That is no longer "a piece of paper" but an impressive thing with a golden tint. Nice, isn't it?

Testing the cooling system

It doesn't make sense testing the efficiency of the cooling system for ASUS EN9800GX2 TOP - we have done that repeatedly before - we're more interested in the unique cooling system for ASUS EAH3850 X2. We'll be testing it using the Firefly Forest test from the 3DMark 06 suite. The test conditions: the resolution 1600x1200, 4-X FSAA, and 16-X AF. After nine runs of the test we produced the following results:

The heating of GPUs did not exceed 65 C, all would have been fine but for one thing: the rotational speed of the fans was constant at the "100%" mark. Their speed is not adjustable with drivers, nor Riva Tuner was able to fix that. Fortunately, ASUS Smart Doctor helped.

It offers 3 modes, with the best one called Smart Cooling. It allows setting various thresholds for the fans' rotational speeds depending on the temperature, which lets smoothly adjusting the fans' speed. In the automatic mode, the fans rotate slowly only in the 2Dmode, and in the 3D mode their speed rises to the maximum. To attain the best result, you'd have to play with the temperature thresholds, which will certainly take a while and some efforts from the user.

Overclocking

ASUS EN9800GX2 is factory-overclocked: its frequencies are 669/1674 MHz for the GPUs and 2124 MHz for the video memory, while the recommended frequencies are 600/1512 MHz for the GPUs and 2000 MHz for the video memory. Note that these frequencies are very close to those recommended for GeForce 9800GTX - 675/1674 MHz for the GPU and 2200 MHz for the video memory. That is quite good for our idea, but we'll tell about it later. Now regarding ASUS EAH3850 X2. To start with, the driver by AMD recognized ASUS EAH3850 X2 as Radeon HD3850 X2:

Therefore, it is not mandatory to use drivers by ASUS. If an 8-pin connector is used to apply power to the video card, the "ATI Overdrive" tab in the CCC panel becomes available, however, it is able adjusting the clock speeds within very narrow ranges. As was found out, to operate ASUS Smart Doctor it is also required to plug in an 8-pin connector, otherwise the utility displayed an error message on startup. Unfortunately, there is no right adapter in the package bundle, so if your PSU is not fitted with a respective connector, then to attain the required effect you can plug in a 6-pin connector from the PSU to the 8-pin connector of the video card's power connector, whereas the two remaining pins in the connector of the video card should be closed.

As is the case with Radeon HD3870 X2, you can't disable the CrossFire mode for ASUS EAH3850 X2 - the drivers simply don't have the right tab. It's a pity, because the need for that may rise, for example, if the CrossFire mode results in performance drops, which happens quite often. The frequencies for ASUS EAH3850 X2 are 668 MHz for the GPU and 1656 MHz for the video memory, the way for the single Radeon HD3850. To overclock the card, we had to use the proprietary ASUS Smart Doctor utility because Riva Tuner is able only adjusting the frequency for one of the graphic chips. We were able to overclock ASUS EAH3850 X2 to 750/1926 MHz - the ASUS' utility is unable to set a frequency higher than that.

The Tests

We'll be running the tests with the following configuration:

To test Radeon video cards, we used Catalyst 8.6 drivers, for GeForce - ForceWare 175.19. The purpose of today's tests is not only to explore the performance level of ASUS EAH3850 X2 but also to study the effect from using the multi-GPU technology CrossFire and compare it against NVIDIA's SLI technology. In our tests, we'll be using the following video cards:

• ASUS EAH3850 X2, a dual-GPU video card based on AMD RV670 chips, uses the CrossFire technology.
• Radeon HD3850, single-GPU video card based on the AMD RV670 chip.
• ASUS EN9800GX2 TOP, dual-GPU video card based on NVIDIA G92 chips, uses the SLI technology.
• GeForce 9800GTX, single-GPU video card based on NVIDIA G92.
• Radeon HD4870, AMD's most recent single-GPU video card, very close in price to the first and fourth video cards.

We'll be running tests in both Windows XP and Windows Vista using the same kit of gaming tests. That is required because the drivers for these operating systems may differ in quality. For instance, AMD is more oriented towards Windows Vista. So, off we go - let's start with the test results for 3DMark.

At these tests, ASUS EAH3850 X2 showed a bit lower results than ASUS EN9800GX2. Not bad - a second place, but the alignment of forces may change in gaming tests. We'll be running further tests in four resolutions and quality modes, and the results produced in Windows XP and Windows Vista will be interlaced for better visual experience.

At Call of Duty 4 under Windows XP, we see a performance gain due to both CrossFire and SLI.

In Windows Vista, the alignment of forces is unchanged, so you can play Call of Duty 4 in both operating systems comfortably. That applies to first of all to the multi-chip configurations, and now you will see why.

At Need for Speed Pro Street Racing, the CrossFire technology works at a loss and demonstrates a performance drop rather than gain. The issue is not new, but for some unknown reasons it has not been fixed yet. On the contrary, the SLI has demonstrated its best.

The issue is still there in Windows Vista - the CrossFire combination loses to the single-chip video card!

At Crysis in Windows XP, the dual-chip ASUS EAH3850 X2 demonstrated a small performance gain as compared to the single-chip Radeon HD3850. The SLI technology demonstrated a more substantial performance gain as compared to the single-chip video card, which makes it more efficient than AMD's technology.

For Windows Vista, we got a different result: the dual-chip ASUS EAH3850 X2 is much faster than the single-chip Radeon HD3850, and the dual-chip ASUS EN9800GX2 TOP managed to lose to the single-chip GeForce 9800GTX in all the resolutions, except 1680x1050. We presume that was caused by the shortage of video memory for NVIDIA video cards.

At Call of Juarez in Windows XP, the CrossFire technology has always demonstrated superb results. The SLI technology is on par with it, so there are no issues about the game in Windows XP.

In Windows Vista at Call of Juarez with the SLI enabled, we came across the old issue – shortage of video memory. Interestingly, there hasn't been such issue so far with a single-chip video card in this game. We found issues with the CrossFire as well - the game was running in stutters.

At Race Driver:GRID, ASUS EAH3850 X2 showed the same issues as those found in Need for Speed Pro Street Racing. The CrossFire resulted in a performance drop as compared to a single-chip video card, plus issues with image. For instance, instead of a radar there appeared a violet square instead. But there were no complaints about the SLI technology ASUS EN9800GX2 TOP - demonstrated a good performance gain as compared to the single-chip GeForce 9800GTX.

In Windows Vista, the situation radically changed: ASUS EAH3850 X2 demonstrated a greater performance boost as compared to the single-chip Radeon HD3850, there were no issues with the image, the game was running very smoothly. The SLI also proved to be up to the mark - ASUS EN9800GX2 TOP demonstrated a sharp performance boost as compared to the single-chip GeForce 9800GTX, nor there were other issues with the game either.

Final Words

As we know, AMD is opposing its dual-chip solutions to NVIDIA's most powerful single-chip video cards, assuming that multi-chip video cards and combinations of video cards will be the winners in future. However, our today's tests have once again demonstrated that the CrossFire technology is not yet perfect. It is a pity, but there are just a few games at which this multi-chip technology results in a substantial performance gain. On the other hand, much depends on the operating system - on the average, CrossFire runs better in Windows Vista than in Windows XP. NVIDIA has not put stakes upon multi-chip solutions as AMD, however SLI works a bit better. Certainly, AMD should improve the drivers, otherwise it will be too hard to compete against NVIDIA. Perhaps, the right drivers are already on the way as is the announcement of the dual-chip flagship Radeon HD4870 X2? We do build hopes of that, otherwise AMD will not be able to create a competitor to GeForce GTX280.