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NVIDIA GeForce 7900 GTX, 7900 GT and 7600 GT Preview

by Ryszard Sommefeldt on 9 March 2006, 14:05

Tags: Nvidia Geforce 7900 GTX, NVIDIA (NASDAQ:NVDA)

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FP16 Blend Performance and Performance Summary

Before we conclude things, here's a quick benchmark that tests FP16 blending performance. Far Cry's HDR path on GeForce 6-series a later hardware (1.33 patch or later) uses FP16 blending, which everything since (and including) NV40 can accelerate in hardware.

FP16 Blending Performance

FP16 Blending Performance

The thing to note that G71 at G70's clocks performance faster in our test level with HDR on. That's what NVIDIA promised, and that's what turns out to be the case. The ROP is further optimised for reading and writing from an FP16 surface in card memory (which consumes more memory bandwidth than nearly anything else the GPU can do), which increases the performance.

NVIDIA have re-engineered the ROP in recent times to allow update of large rendertargets to happen more efficiently (witness a 'double' colour write rate), which is useful for all manner of post-processing effects (to name just one use).

Performance Summary

Compared to G70, G71 offers improvements in performance in a number of areas at the same clock rates. FP16 blend performance is up usefully, as is texture rate, and texture latency is down. Compared to NV43, G73 is an even bigger step forward. Bundled in with the improvements G71 sports, G73 gets beefed up FP ALUs, tweaked VS hardware, and the chip is usefully wider from VS to ROP.

Both are clocked faster (at the high end at least) than the top SKUs produced by the GPUs they replace, too. So performance is up across the board, both per clock and in terms of final clock rates obtainable.

While not shown (quite yet), 7600 GT is usefully faster than 6800 GS and X1600 XT, which sit the main competitors to that new product. In that respect, there's a new mid-range performance winner in town, all other things unconsidered.

On the 7900 side, 7900 GT has the potential to be the equal of the hilariously expensive and hard to obtain GeForce 7800 GTX 512, and it largely will match X1800 XT, while 7900 GTX almost has the measure of ATI's Radeon X1900 XT and XTX.

With 7600 GT dominating the mid-range, it's more than a little strange to not say the same thing about NVIDIA's new high-end product. The 7900 GTX can outrun Radeon X1900 XTX, but in general it won't. Performance is competetive, but if you're concerned with absolute performance in modern games at high resolution, NVIDIA's new flagship G71-based SKU fall slightly short.

All that said, it's time to focus on the rest of the things that make graphics products stand out and leave store shelves. Read on for our final thoughts that encompass not just performance, but price, availability, IQ and physicals.