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The 8800 GT up close
What the 8800 GT lacks in functional units, it largely makes up in clock speed. The 8800 GT's official core clock speed is 600MHz, and its 112 SPs run at 1.5GHz. The card's 512MB of GDDR3 memory runs at 900MHz—or 1.8GHz effective, thanks to the memory's doubled data rate.


MSI's NX8800GT

Here's a look at MSI's rendition of the GeForce 8800 GT. Note the distinctive MSI decal. This card is further differentiated in a way that really matters: it comes hot from the factory, with a 660MHz core clock and 950MHz memory. This sort of "overclocking" has become so common among Nvidia's board partners, it's pretty much expected at this point. MSI doesn't disappoint.

I don't want to give too much away, since we've measured noise levels on a decibel meter, but you'll be pleased to know that the 8800 GT's single-slot cooler follows in the tradition of Nvidia's coolers for its other GeForce 8800 cards. The thing is whisper-quiet.

The sight of a single-slot cooler may be your first hint that this is not the sort of video card that will put an ugly dent in your credit rating. Here's another hint at the 8800 GT's mainstream aspirations. Nvidia rates the power consumption of the 8800 GT at 110W, which makes the single-slot cooler feasible and also means the 8800 GT needs just one auxiliary PCIe power connector, of the six-pin variety, in order to do its thing.


The 8800 GT sports a single six-pin PCIe aux power connector

Another place where the 8800 GT sports only one connector is in the SLI department. That probably means the 8800 GT won't be capable of ganging up with three or four of its peers in a mega-multi-GPU config. Two-way SLI is probably the practical limit for this card.

Here's the kicker, though. 8800 GT cards are slated to become available today for between $199 and $249.

Doing the math
So that's a nice price, right? Well, like so many things in life—and I sure as heck didn't believe this in high school—it all boils down to math. If you take the 8800 GT's seven SP clusters and 112 SPs and throw them into the blender with a 1.5GHz shader clock, a 256-bit memory interface, along with various herbs and spices, this is what comes out:

Peak
pixel
fill rate
(Gpixels/s)
Peak texel
sampling
rate
(Gtexels/s)
Peak bilinear
texel
filtering
rate
(Gtexels/s)
Peak bilinear
FP16 texel
filtering
rate
(Gtexels/s)
Peak
memory
bandwidth
(GB/s)
Peak
shader
arithmetic
(GFLOPS)
GeForce 8800 GT 9.6 33.6 33.6 16.8 57.6 504
GeForce 8800 GTS 10.0 12.0 12.0 12.0 64.0 346
GeForce 8800 GTX 13.8 18.4 18.4 18.4 86.4 518
GeForce 8800 Ultra 14.7 19.6 19.6 19.6 103.7 576
Radeon HD 2900 XT 11.9 23.8 11.9 11.9 105.6 475

In terms of texture sampling rates, texture filtering capacity, and shader arithmetic, the 8800 GT is actually superior to the 8800 GTS. It's also quicker than the Radeon HD 2900 XT in most of those categories, although our FLOPS estimate for the GeForce GPUs is potentially a little rosy—another way of counting would reduce those numbers by a third, making the Radeon look relatively stronger. Also, thanks to its higher clock speed, the 8800 GT doesn't suffer much in terms of pixel fill rate (and corresponding AA grunt) due to its smaller ROP count. The 8800 GT's most noteworthy numbers may be its texture sampling and filtering rates. Since its SPs can grab twice as many texels per clock as the G80's, its texture filtering performance with standard 8-bit integer color formats could be more than double that of the 8800 GTS.

Performance-wise in graphics, math like this isn't quite destiny, but it's close. The only place where the 8800 GT really trails the 8800 GTS or the 2900 XT is in memory bandwidth. And, believe it or not, memory bandwidth is arguably at less of a premium these days, since games produce "richer" pixels that spend more time looping through shader programs and thus occupying on-chip storage like registers and caches.

Bottom line: the 8800 GT should generally be as good as or better than the 8800 GTS, for under 250 bucks. Let's test that theory.