XFX does the GTS with the XXX
We should probably start at the beginning with the G80 GPU that powers the GeForce 8800 lineup. This massive graphics chip has 680 million transistors, and its die area could practically be measured in square miles. If you're unfamiliar with it, you should go read our review of the GeForce 8000 in order to come up to speed. The G80 is the first PC graphics processor with a unified shader architecture and support for Direct X 10, and both of those things are critical buzzword phrases for the future of graphics marketing. Fortunately, we found the G80's performance to be excellent, and we think it produces higher quality pixels than any other desktop graphics chip, as well. Both its performance and image quality are second to none.
The GeForce 8800 GTS started life as a product of the world's smallest chainsaw when Nvidia deactivated some portions of the G80 GPU for the sake of product segmentation. In the GTS, the G80 has two of its eight clusters of stream processors and one of its six ROPs partitions disabled. That leaves the GTS with a total of 96 stream processors and a 320-bit path to memory, down from 128 SPs and 384 bits in the GeForce 8800 GTX. Clock frequencies are also down in the GTS. The primary GPU clock, or core clock, is 500MHz. The stream processors run at 1.2GHz, and the card's GDDR3 memory is clocked at 800MHzor 1.6GHz effective, for those of you keeping score at home.
The big change in today's new product is simply a reduction in memory size from 640MB to 320MB, nothing more. 320MB versions of the GTS have the same 320-bit path to memory as the 640MB versions. The smaller amount of onboard memory will affect performance, of course, but only in certain scenarios, like when applications need to store lots of data or when running at really high resolutions with lots of edge and texture antialiasing enabled. We'll dig into that when we look at our test results.
But first, here's a look at our test subject, the XFX GeForce 8800 GTS 320MB XXX edition.
Why is it called the XXX edition? Good question. I've spent hours with this card, and I think it's just a tease.
Still, this tease has its virtues, including a higher out-of-the-box frequency than the usual GTS. The XXX edition's core GPU clock is 580MHz, and its memory runs at 900MHz. As for its SPs, I don't know the exact frequency, but Nvidia says SP clock speeds are tied to the core GPU clock, so the SP clock frequency should rise proportionately with core speed.
XFX says the suggested retail price for the XXX edition is $334.99or $335 to you and me. They're also selling an ExTreme edition with 560/850MHz core and memory clocks for $310 and a bone-stock 500/800MHz version for $300. The core clock speeds for the XXX and ExTreme cards are actually higher than they are for the corresponding 640MB versions, raising the intriguing possibility that the card with less memory and a lower price could prove faster in some applications.