Nvidia GeForce 7950 GX2 review

Nvidia's GeForce 7950 GX2 graphics card should be a PC gamer's dream. For a price of around £400 (if you shop around online), the card gives you the same 3D gaming performance as you would get from two GeForce 7900 GTX cards at half the cost. And because Nvidia has crammed two graphics processors onto a single card, you lose only half as much interior desktop real estate.

But the problem is that the GeForce 7950 will be an entire generation behind in roughly six months. We can deal with the iterative updates that happen within a generation of 3D chips, but the forthcoming shift from DirectX 9 hardware -- such as the GeForce 7950 -- to DirectX 10-based gear later this year presents too monumental a change to justify spending £400 on the card now. It's annoying, because there's a lot to like here.

Previously, when you wanted two 3D cards inside your PC (for the purposes of fast, high-resolution, high-detail gaming), you needed to buy two cards from ATI or Nvidia, plug each card into your PC's power supply, and join them together via either Nvidia's internal SLI connector or ATI's external CrossFire dongle. Through that process, you limit your expansion options -- the bulky cards block adjacent slots -- and increase the likelihood of requiring a massive power supply. Thanks to its all-in-one dual-3D-chip package, the GeForce 7950 GX2 solves all of those problems.

A single GeForce 7950 GX2 still takes up two expansion slots' worth of space, but instead of losing two adjacent slots, now you lose only one. And because it requires just a single connection to your PC's power supply, you don't need the 600W, 750W, or 1kW power supplies that have become far too common. Instead, Nvidia recommends only a 400W power supply to power a single GeForce 7950 GX2, a marked improvement.

The GeForce 7950 GX2 is much more compact than Nvidia's first dual-3D-chip card, the GeForce 7900 GX2, which was available only from system vendors

So it's neither the design of the card nor its requirements that hold us back, but rather the 3D chips themselves. The GeForce 7000 series has been a solid performer for Nvidia. It helped usher in the dual-card SLI era, and even though ATI's Radeon X1000's can jump through a few more hoops, we think most gamers would argue that this current generation of 3D chips has served the gaming public well. If that sounds like an epitaph, you're not far off. The problem is Windows Vista, or more specifically, Vista's updated multimedia programming interface, DirectX 10.

DirectX is Microsoft's Rosetta stone for combining hardware and software. As long as software programmers and hardware developers design their products to cue into DirectX, compatibility should be guaranteed. The current version for Windows XP is DirectX 9.0c. Microsoft has stated that Vista will support DirectX 9 software and hardware but that the OS will ship with DirectX 10. The GeForce 7950 GX2 (along with the rest of the GeForce 7000 series), however, is a DirectX 9 part. This means that while it will work with Vista, it won't support the latest and greatest 3D features, so your £400 investment will be out-of-date only six months after you buy it, assuming Microsoft hits its targeted January Vista release date. While Nvidia (or ATI) has yet to announce a DirectX 10 chip, you can bet that such cards will be out or will be very near release by the time Vista launches.

All of which is too bad, because the GeForce 7950 GX2 really is a fast 3D card. Its core specs aren't as fast as Nvidia's single-card flagship, the GeForce 7900 GTX. That card has a 650MHz clock speed for the GPU and 800MHz for the memory, whereas the GeForce 7950 GX2 has a 600MHz GPU clock and only 500MHz for each chip's 512MB of DDR3 RAM. We're not surprised by the clock speed reductions given the heat and power issues inherent to running two fast GPUs in a single-slot package, but we were surprised by the performance results. (Thanks to Sarju Shah, GameSpot's illustrious associate hardware editor, for sharing his benchmark scores with us).

3DMark 2005
(Higher scores indicate better performance)

1,280x1,024

-pixel resolution

512MB ATI Radeon X1900 XT Crossfire mode

9010 

512MB Nvidia GeForce 7900 GTX SLI

8835 

512MB Nvidia GeForce 7950 GX2

8560 

512MB Nvidia GeForce 7900 GTX

6018 

512MB ATI Radeon X1900 XT

5946 

The Elder Scrolls IV: Oblivion (in fps)
(Longer bars indicate better performance)

1,600x1,200-pixel resolution (max quality, no AA, no AF)

512MB Nvidia GeForce 7950 GX2

39 

512MB Nvidia GeForce 7900 GTX SLI

38 

512MB ATI Radeon X1900 XT Crossfire mode

35 

512MB ATI Radeon X1900 XT

35 

512MB Nvidia GeForce 7900 GTX

31