Asus EN8800GT

Verdict: Almost as fast as the GeForce 8800 GTX and nearly half the price.

With Christmas approaching, manufacturers are frantically churning out their merchandise. New products range from silly stocking-fillers to huge items that won't even fit under the tree. The new GeForce 8800 GT graphics card slots in between these two extremes - it's a long graphics card with a single-slot cooler on top. This is the card that Nvidia hopes you'll buy this Christmas, but why?

This is the first PCI-E 2.0 card we've seen - so, obviously, it's almost twice as good as those old PCI-E 1.1 cards, right? As ever, matters aren't so simple. All PCI-E 2.0 offers over PCI-E 1.1 is twice the usual bandwidth (if the chipset supports PCI-E 2.0, which currently applies only to the expensive Intel X38) and extra power through the slot. Determining whether the extra bandwidth affects gaming performance is nearly impossible, as you can't switch between PCI-E 1.1 and PCI-E 2.0 on an X38 motherboard. We'd have to test on different motherboards, which would invalidate any comparative results. At least PCI-E 2.0 is backwards compatible with PCI-E 1.1, so this card will work in any motherboard with a 16x PCI-E slot.

First, we tested to ascertain whether an X38 board could power the card through just the slot, thus avoiding the need for a separate PCI-E power cable.

Unfortunately, the card wailed like a distressed pre-pubescent on helium until we plugged in the 6-pin PCI-E connector. With a PCI-E 2.0 slot providing 150W of power (double that of a PCI-E 1.1 slot), the GeForce 8800 GT resides in the high-energy bracket of GPUs. However, our test system drew only 240W from the mains when gaming, making the GeForce 8800 GT 6W less energy-hungry than the 320MB GeForce 8800 GTS.

The low power consumption is good going considering the specs of the new GPU, codenamed G92. There are 112 stream processors running at 1.5GHz, while the rest of the GPU runs at a respectable 600MHz. This means that the core of the 8800 GT runs faster than that of the 8800 GTX (575MHz), while the stream processors are clocked at the same speeds as on the 8800 Ultra.

A little crude maths shows just how impressive the new GPU is. Multiply the number of stream processors by the speed at which they operate, and you have the number of peak stream processor operations per second. As it's the stream processors that render the eye candy, this figure is fairly indicative of performance. The 112 stream processors in the 8800 GT run at 1.5GHz, so this GPU has a peak of 168 billion stream processor operations per second. The 8800 GTS (either version) has only 96 stream processors running at 1.2GHz, providing 'only' 115.2 billion operations per second. Even the £330 8800 GTX only beats the 8800 GT by 4.8 billion stream processor operations with its 128 stream processors running at 1.35GHz. As we said, the 8800 GT has a faster core speed, so it can handle the outcome of the shader operations in its 16 ROPs (as opposed to the 20 of the 8800 GTS and the 24 of the GTX) quicker than any 8800 card, bar the Ultra. Making a similar comparison with a Radeon HD 2900-series card is pointless, however, as the maths we used assumes that each stream processor can do the same work per cycle. The ATI HD-series stream processor architecture is different to that of the Nvidia 8-series, so our calculations would make for a meaningless comparison.

Cramming this performance into a GPU that can be cooled by a single-slot cooler would be difficult if the GPU were not made using a 65nm manufacturing process. The benefits of making a silicon chip from smaller transistors are massive. The chip is physically smaller, so you can make more of them from a single wafer of silicon. Smaller transistors also tend to switch faster, so you can ramp up the clock speeds. The final benefit is that a smaller transistor requires less power to switch - this is the key reason why the 8800 GT can use a single-slot cooler and quiet fan.

The GPU may be advanced, but there are compromises in other areas. For example, the 512MB of RAM is accessed through a 256-bit bus rather than the 320-bit bus on the GTS cards or a 384-bit bus on the GTX.

The Asus EN8800GT we were sent uses the reference Nvidia cooler but, as you can see, it sports a great big Company of Heroes: Opposing Fronts sticker. A copy of the game is included in the box, along with a floppy CD wallet, a PCI-E power adaptor and a component video cable.

Performance

As clever as this chip sounds, it has to be able to cut it with games. So it's good news for the 8800 GT that it stormed through our game benchmarks with scores we've only seen previously from £300+ cards.

F.E.A.R. failed to challenge it in any way, even at 1,920 x 1,200 with 4x AA and 16x AF, delivering a smooth minimum frame rate of 29fps and an average of 59fps. This is slightly faster than a 640MB 8800 GTS, which costs around £235 - an impressive feat considering the GT's narrower memory bus and lower quantity of RAM. The frame rates at 1,680 x 1,050 were also impressive, with a minimum of 54fps and an average of 97fps, while the 640MB 8800 GTS scored a minimum of 52fps and an average of 89fps.

Need for Speed: Carbon was a tougher challenge, although the 8800 GT again put both GeForce 8800 GTS variants to shame. With a minimum frame rate of 45fps and an average of 58fps at 1,680 x 1,050, it nearly matched the £330 8800 GTX for speed, with the latter only running a measly 2fps faster. The £235 Radeon HD 2900XT struggled in comparison, scoring a minimum of only 37fps and an average of 47fps. The game was even playable at 1,920 x 1,200 - the minimum of 35fps and average of 46fps are only a few frames per second shy of the 8800 GTX.

Performance in S.T.A.L.K.E.R. was similar, with a minimum of 39fps and an average of 52fps in the 1,680 x 1,050 test. The 8800 GTX ran the game at a minimum of 41fps and an average of 54fps in this test. Jumping up to 1,920 x 1,200 didn't slow the 8800 GT much; it managed a minimum of 33fps, compared to the 40fps scored by the 8800 GTX.

We could overclock the 8800 GT to a core speed of 660MHz and a memory speed of 970MHz (1,940MHz effective) using ATITool 0.26. This gave F.E.A.R an extra 3-6fps in the 1,920 x 1,200 test and an extra 8-14fps in the 1,680 x 1,050, which is well worth an hour of tinkering. However, the GPU becomes very hot and we had to point a 120mm fan at the back of the PCB.

DirectX 10 performance

For DirectX 10 testing, we used Company of Heroes, patched to 1.7, and World in Conflict. All the tests were run on the same PC as the DirectX 9 tests, but on a Vista partition on the hard disk. We started testing at 1,680 x 1,050, using 2x AA and 4x AF for World in Conflict, and 2x AA for Company of Heroes.

The results were bad; the World in Conflict in-game benchmark ran at a minimum of 15fps and an average of 25fps in DirectX 10 mode, compared to a 16fps minimum and 32fps average in DirectX 9 mode. The average frame rates scale with graphics power, and to obtain the comfortable figures we saw, you need to drop the resolution to 1,280 x 1,024 with no AF. We saw an average of 30fps in DirectX 10 mode and 37fps in DirectX 9 mode.

Company of Heroes was much the same story. DirectX 10 mode at 1,680 x 1,050 saw a minimum frame rate of 8fps and an average of 22fps. In DirectX 9 mode, this rose to a minimum of 16fps and an average of 22fps. Dropping to 1,280 x 1,024, but retaining 2x AA, saw equally disappointing scores: a minimum of 9fps and 25fps in DirectX 10 and DirectX 9 modes respectively. Even at 1,024 x 768 with no AA, Company of Heroes managed a minimum of only 24fps and an average of 47fps in DirectX 10 mode.

To see if this was the work of the early-release ForceWare 167.26 Vista driver - as we experienced random crashes in our DirectX 10 tests - we tried the same tests (albeit, in DirectX 9 modes only) in XP. Company of Heroes at 1,680 x 1,050 with 2x AA ran at a minimum of 36fps and an average of 59fps. World in Conflict at 1,680 x 1,050 with 2x AA and 4x AF returned a minimum frame rate of 20fps and an average of 34fps, which is just about playable.

Conclusion

The 8800 GT is awesome. It's much faster and slightly more energy-efficient than its 8800 GTS predecessors, and it costs the same amount. Our only word of caution is that the BETA Vista drivers left a lot to be desired, although this should be sorted out by the time the card goes on sale.

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• DFI Lanparty DK P45-T2RS PLUS - Motherboards
• Hyundai W240D-PVA - TFT monitors
• Intel X25-M Mainstream SATA SSD - Hard disks / storage
• S.T.A.L.K.E.R. Clear Sky - Games
• LanCool Metal-Boned K10 - Cases
• Asus Maximus II Formula - Motherboards