Introduction

Nvidia's SLI (Scalable Link Interface) has been around for sometime now but up until recently SLI meant linking just two graphics cards together. Not anymore. The white coats at NVidia have been hard at work creating a flagship gaming platform enabling not two but FOUR GPU's in the form of the mighty 9800GX2 x 2. These dual-GPU cards are advertised as the pinnacle of graphics processing technology. What's that you say? Quad SLI aint new! Well OK, Quad SLI started out in life in the form of the 7950GX2 released in mid 2006 but ultimately it fell flat on its face due to scalability problems and Nvidia fell short of delivering better support due to the diminished uptake in the new technology. While the 7950GX2 worked on its own (SLI in a dual PCB - single card solution), Quad SLI performance was ultimately dismal. While I don't agree with the way Nvidia abandoned those stuck with the cards I can understand why they did it as with a new operating system and DirectX10 on the horizon, Nvidia had bigger fish to fry.

Luckily, the green side of the GPU market have forgiven Nvidia for their past behaviour and have been rewarded with some stunning GPU releases, namely the 8800 GTX. It's been a long time since we had such a fantastic, long lasting, king of performance. Not since the ATI 9700 days has there been a single card dominating the performance sector and despite their best efforts, ATI just could not compete on the same level as Nvidia. You would be forgiven then for believing Nvidia were resting on their laurels as it had been over a year before we saw a 'new' king of the hill. So what pushed Nvidia out of hibernation? CrossFireX. ATI's answer to grabbing back the performance crown. ATI GPU's simply did not have the raw power to dethrone the mighty G80, so instead ATI took a different approach and simply stuck 2 GPU's on the same card in the form of the 3870x2. Now the 3870 is no slouch so linking two of them together on the SAME PCB, with the further possibility of using 4 of the cards in CrossFireX was sure to ruffle a few feathers over at the Nvdia house and kick them into action.

 

So here we are today with the 9800GX2, Nvidia's flagship card(s). I say cards as although the GX2 is a single slot PCIe solution it is still two PCB's linked together rather than adapting to the ATI approach of putting both GPU's on a single PCB. This time however, Nvidia have wrapped them up in a sleek looking metal frame and rather than looking like the Star destroyer that was the 7950GX2, the 9800GX2 looks strikingly like the Monolith from "A Space Odyssey".

To evaluate the performance of Quad SLI we will be pitching the offerings from XFX against its arch rival the 3870X2 in Quad Fire (CrossfireX) which again is 4 GPU's linked together in a 2+2 format hence comparisons will be made throughout this review in an attempt to discover which solution is best for you.

Lets take a look at the GX2 in greater depth...