The GeForce FX has a lot of potential. The specifications released at the product's launch last November were quite impressive. The fastest of nVidia's new cards, officially called the GeForce FX 5800 Ultra, is clocked to incredible speeds: 500MHz for the core chip and 500MHz (1GHz effective) for the double-data rate 2 (DDR2) memory. And it has next-generation features that go beyond even the basic requirements for full Microsoft DirectX 9 support. But real-world performance in current games is what makes or breaks any high-end graphics card, and the GeForce FX has its work cut out for it in facing the current champ, the ATI Radeon 9700 Pro. We've had an early opportunity to test the card, and although it's a huge step up from the GeForce4 Ti 4600, it doesn't seem to offer any substantial performance increase over the Radeon 9700 with current games.
A hot chip
nVidia and ATI took slightly different approaches to getting lots of performance out of their high-end cards. nVidia has stepped up to a new generation of memory, DDR2, that's capable of much higher speeds (200MHz or more above regular DDR), but at the cost of increased power usage and some additional latency. ATI's Radeon 9700 and Radeon 9700 Pro cards have wider pathways between the chip and the local memory, so even with the memory at just 310MHz, the Radeon 9700 Pro offers more raw bandwidth than the GeForce FX 5800 Ultra. A direct result of the GeForce FX's high clock speeds is that the chip and memory both run very hot, and the card consumes more power than the standard AGP bus can provide. Like 3dfx's Voodoo5 5500 and ATI's recent Radeon cards, the GeForce FX cards must be connected directly to a PC's power supply by means of a standard four-pin hard drive power cable. Some drastic measures are required to dissipate all the heat that the GeForce FX produces. As you can see in photos of the card, there's an extremely large cooling device that covers the top of the chip and the memory, as well as a low-profile copper heat sink on the other side to cool the memory on the back of the card. Not only does this large cooler take up an additional PCI slot inside the PC's case, it also generates quite a bit of noise -- much louder than practically any CPU cooler. Fortunately, these extra precautions are really critical for only the high-end GeForce FX 5800 Ultra card. nVidia has also announced a couple of workstation cards and a gaming variation called the GeForce FX 5800, which feature lower clock speeds that may allow for less radical cooling. Retail cards based on the 5800 Ultra are expected to cost around £250; the regular 5800 will cost somewhat less.
nVidia has finally released reference boards that are representative of the performance we'll see from retail graphics cards starting next month. Although we haven't had much time to test the GeForce FX 5800 Ultra, the benchmarks we did run tell an interesting story.
The standard run of the 3DMark 2001 SE benchmark sums up how the nVidia and ATI cards compare. The GeForce FX's biggest lead comes at a resolution of 1,600 x 1,200 without anti-aliasing, and even then it's a difference of less than 10 percent. At other settings, the Radeon 9700 Pro delivers results that are practically identical or even better than those of the nVidia card. The GeForce FX's speed is still quite apparent relative to the GeForce4 Ti 4600, particularly at the highest resolutions with anti-aliasing turned on, where the increased memory speed and efficiency comes into play The surprise is that nVidia's best efforts haven't resulted in a card that's any faster than the Radeon 9700 Pro. nVidia says the drivers are practically ready to ship (they're reported to be stable, compatible, and complete), but performance should improve a bit with optimisation over the next couple of months. The 3DMark 2001 SE results provide some insights into the card's mixed performance. Although the DirectX 9-based 3DMark 2003 is in the works, the 2001 SE benchmark is still a reliable indication of raw performance under DirectX 8. The theoretical tests break down performance in a few critical areas, and the GeForce FX does particularly well in the fill-rate, eight-light geometry and vertex-shading tests. The advanced vertex shader, written specifically for the ATI hardware features in DirectX 8.1, is the one place where the Radeon 9700 Pro has a clear advantage. In any case, these theoretical tests give an indication that the GeForce FX will be an outstanding card in upcoming games -- such as Doom III -- that use advanced lighting techniques based on many textures and vertex shaders.
The bottom line
Surprising as it may be to those who have followed nVidia's consistent success over the last few years, the graphics giant's newest offering doesn't look as though it will be the clear performance leader it was promised to be. With the current drivers, the GeForce FX 5800 Ultra doesn't surpass the Radeon 9700 Pro by any significant margin. That's a big disappointment for those who've been holding off on a PC upgrade to get nVidia's newest card. ATI seems to have won this round by virtue of delivering its card sooner. And rumour has it that ATI has a faster card up its sleeve for release just months after the GeForce FX ships.