Nvidia GeForce 9800 GX2

Verdict: OMG! Nvidia's new graphics card can play Crysis at high resolutions.

When it comes to graphics cards, all the recent headlines have centred on mid-range, £100-200 cards, such as the ATI Radeon HD 3850 and the Nvidia GeForce 8800 GT. This focus on sensibly priced kit even extended to the launch of the GeForce 9-series: it debuted as a mid-range GPU in the shape of the Nvidia GeForce 9600 GT. At the time, we wondered why Nvidia was breaking with tradition and kicking off a new series with a mid-range offering. Persuading the world that the GeForce 9-series is hands down, no questions-asked, just plain better than the GeForce 8-series is a tough ask with a £120 GPU that only has 64 stream processors. Nvidia isn’t going to do that with a £120 card, but it just might with its second 9-series offering - the massive GeForce 9800 GX2.

7950 GX2 vs 9800 GX2
The ‘GX2’ name was previously used for GeForce 7950 GX2, a dual-PCB, dual-GPU card, and this is the approach Nvidia has taken with 9800 GX2. Yes, this graphics card is actually made from two graphics cards squeezed together into one package. The cards in question are closely based on the 512MB GeForce 8800 GTS, though with some modifications in order to fit them into one handy, 10.5in long metal box. The circuit-boards of the cards have holes cut in them to allow air to flow into and around the chunky black box cooler. Unlike the 7950GX2, which stacked card, cooler, card, cooler on top of each other, like toppings on a pizza, in the 9800 GX2, the PCBs sandwich one big HSF between them.

Nvidia has also downclocked the GPUs, presumably to reduce the internal temperature of the card. A regular 512MB GeForce 8800 GTS GPU has a core speed of 650MHz with its 128 stream processors running at 1.625GHz - the two GPUs of the GeForce 9800 GX2 each have 128 stream processors, but these run at 1.5GHz, and the GPUs themselves are clocked at 600MHz. Both GPUs have 512MB of 1GHz (2GHz effective) GDDR3 memory. Despite scaling back the speeds, the GeForce 9800 GX2 still gets extremely hot, even when it’s not doing much, so a well-ventilated case is a must.

Also bear in mind that the GeForce 9800 GX2 has two power connectors – one 6-pin and one 8-pin – and that Nvidia claims the card consumes 197W. A bit of maths (197W/12V) tells you that you’ll need at least 16.4A on your 12V rail, which actually isn’t that much considering that a typical 700W PSU will have 20A on each of its 12V rails. Our test PC drew 409W from the wall at peak during our graphics stress test, so you’d want a PSU that’s rated at around 700W or more anyway (it’s best to have some headroom, as the components in the PSU will be less stressed, run cooler and be more efficient at delivering the power).

The GeForce 9800 GX2 is also 10.5in long and weighs 1.1kg, so fitting in a small case is an ambitious task and you’ll certainly want to screw the card in securely. If you want to see inside it, check out our video in which we take the 9800 GX2 apart.

IT'S ONE CARD, NOT TWO
The GeForce 9800 GX2 can legitimately claim to be a graphics ‘card’ rather than a graphics ‘twincard’ (or whatever) because it has a single PCI-E 2.0-compatible 16x connector and so can fit in any motherboard that can accommodate a dual-slot graphics card. This is a more pertinent point that it may at first seem, as usually you need an SLI-compatible motherboard to make two Nvidia GPUs communicate properly. With the GeForce 9800 GX2, you can get the two GPUs inside it to communicate in any motherboard, be it an Intel P35 or even an AMD/ATI 790FX model. This is thanks to the onboard PCI-E bridge chip that takes the data coming into the card, splits it across the two GPUS, and then helps data move to and from the GPUs. If you take the GeForce 9800 GX2 apart (we wouldn’t recommend it as the internals are quite fiddly) you’ll spot a miniature SLI bridge connector, which does exactly the same job of providing a high-bandwidth inter-GPU connection as the conventional-size bridge of a typical SLI system.

PERFORMANCE
We test using FRAPs, loading a save game in our three test games and playing a section of the game three times at each test resolution. Therefore, our benchmark scores are as indicative of how a card will perform in real life as is possible.

As you’d expect from a £376 card packing two fast GPUs, the framerate scores were incredibly high. This is the first single card that can play Crysis at 1,680 x 1,050, for example, with a smooth minimum of 28fps. We compared the performance against three cards to gauge exactly how much faster the GeForce 9800 GX2 is, and whether it’s worth upgrading if you already have a fast graphics card. The three cards were a pre-overclocked EVGA e-GeForce 8800Ultra Superclocked, a pre-overclocked BFG GeForce 8800 GTS 512MB OC and a stock-speed Sapphire Radeon HD 3870 X2. The EVGA Superclocked Ultra and the BFG 8800 GTS OC could only handle Crysis at 1,024 x 768, with minimums of 28fps and 25fps respectively. This makes the $740 (around £367) that EVGA is listing its card at look a little silly; it’s no surprise that the card’s in short supply as we doubt Nvidia is making many GeForce 8800 Ultra GPUs anymore. The Radeon HD 3870 X2 struggled to play Crysis even at 1,024 x 768 with its stuttery minimum of 23fps.

Need for Speed: Pro Street again proved how much more powerful the GeForce 9800 GX2 is compared to the competition. The game was playable at 1,920 x 1,200 with maximum AF and 4x AA – and still with a mighty minimum frame rate of 65fps. In fact, it’s almost twice as fast as the EVGA Superclocked Ultra which scored 35fps at the same resolution, a score slightly trumped by the BFG 8800 GTS OC which ran the game at 38fps minimum at the same resolution. Again the Radeon HD 3870 X2 lagged behind, only managing to provide a playable minimum frame rate of 27fps at the lesser resolution of 1,680 x 1,050 and with only 2x AA applied.

We suspect the Radeon HD 3870 X2 is held back by driver issues, even though we used the latest Catalyst 8.3 public release driver, as our testing in Call of Duty 4 was incredibly frustrating. We know from previous benchmarking that this game is a tricky one for ATI to run on its dual-GPU card, but the frame rates during testing were all over the place. At 1,680 x 1,050 two runs of the benchmark would give us 16fps as the minimum and the third 31fps. Re-testing would see two runs at 31fps minimum and the third at 11fps minimum. After many runs, we had more scores of 16fps than 31fps, so we had to list this as the speed of the card at this resolution. That means that the Radeon HD 3870 X2 can only reliably play Call of Duty 4 at the poxy resolution of 1,024 x 768 with no AA or AF – not a great result for a card costing around £300.

The Nvidia cards fared much better with Call of Duty 4, with all three cards able to play the game at 1,920 x 1,200 with 4x AA and maximum AF. The BFG 8800 GTS OC only just scrapes by with a minimum of 25fps, while the EVGA Superclocked Ultra scores 30fps minimum. However, the hulking GeForce 9800 GX2 is another notch faster, scoring 45fps minimum. None of the cards, even the GeForce 9800 GX2, could play the game at 2,560 x 1,600 (the native resolution of a 30in TFT) though – the EVGA and BFG cards slumped to sub-20fps minimums while the GeForce 9800 GX2 scored 22fps minimum.

OVERCLOCKING
We couldn’t improve matters either, as no overclocking tool can yet address the two GPUs inside the GeForce 9800 GX2 and overclock them simultaneously. We should highlight the fact that the GeForce 9800 GX2 was tested with the ForceWare 174.53 driver which was written and released to the press on 11 March 2008, while the EVGA Superclocked Ultra and BFG 8800 GTS OC had to be tested with the ForceWare 169.25 which was publicly released on 20 December 2007. It seems incredible that Nvidia is so confident that it nailed the ForceWare 169.25 driver three months ago and hasn’t felt the need to update it, so the cynics in our dark, bitter, journalistic souls suspect Nvidia might not be that interested in getting its GeForce 8800 card to go faster with an updated driver. We also have to report that although the driver we used for testing does support GeForce 9800 GX2 SLI (aka Quad SLI) Nvidia has embargoed the results of Quad SLI testing until 25 March 2008. Expect an update soon.

CONCLUSION
There’s something unlikeable about the GeForce 9800 GX2 – it’s hardly the most well designed card, being hot and bulky, and slapping two PCBs together isn't the most elegant way for Nvidia to make a new high-performance card. For the GeForce 7950 GX2 Nvidia used specially designed power-frugal, cooler-running mobile GPUs to keep the heat output of the card down. For the GeForce 9800 GX2, Nvidia has just clamped two modified desktop cards together and caged the whole thing in black metal. It’s more of graphics brick than a graphics card.

That said, you just can’t argue with the performance it gives – it’s the first card that can play Crysis at 1,680 x 1,050 and makes our other game benchmarks look outdated such is the stellar level of performance even at very high resolutions. Rather than some stealthy assassin of a graphics card that stalks into a game engines and uses trickery and cunning to wrangle big frame rates, the GeForce 9800 GX2 gets the biggest blunt object it can carry, kicks the front door down and batters a game engine into submission. Despite the size and heat of the card, it does justify its price if you want to play modern games at high resolutions. The £200 512MB GeForce 8800 GTS is sufficient for 22in TFT owners, however.

The GeForce 9800 GX2 is on sale now from Scan.

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