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Right then, March 9, 2006. Today is the day that NVIDIA launches no less than three new products into the graphics card arena. I mentioned them already on the previous page. Now I will show you the difference among the models, its placement in the market and of course reveal the new prices.

Let me quickly reintroduce this new threesome to you.

• GeForce 7900 GTX 512 MB - Dual slot cooled - 499 USD
• GeForce 7900 GT 256 MB -Single slot cooled - 299 USD
• GeForce 7600 GT 256 MB Single slot cooled - 199 USD

Please focus on the chart below where I cite the more important specifications. Highlighted in red you'll notice the new products.

Product Name

# pixel processors

# vertex processors

Bus width

Memory Type/Amount

GPU Speed

RAM Speed

GeForce 6800 Ultra **

16

6

256-bit

GDDR3/256MB

400MHz

1100MHz

GeForce 6800 GT

16

6

256-bit

GDDR3/256MB

350MHz

1000MHz

GeForce 6800

12

5

256-bit

GDDR/128MB

325MHz

700MHz

GeForce 6800 LE

8

4

256-bit

GDDR/128MB

320MHz

700MHz

** Not manufactured anymore - Specifications are based on reference numbers. Speeds can differ per model and manufacturer.

Let's talk briefly about the new products one by one

GeForce 7900 GTX 512MB a.k.a G71

What's G71 you ask? This is the codename of the chip from its development stages. Most of you figured we'd see a 32 pixel pipeline product today. And yeah I was hoping it too, but perhaps we were a little too ambitious in our thinking. We'll likely have to wait on the G80 silicon for that. Nonetheless this product is screamingly fast.

So in essence there are three significant changes to the G71 versus G70. A smaller fabrication process at 90nm, a higher core clockspeed and of course faster memory bandwidth. That G71 chip is different, as the transistor count went down. The 7800 GTX for example has 304 million transistors whereas the new 7900 GTX has 278 million, so there are differences for sure. Now we haven't received the whitepapers just yet and I unfortunately had to skip an NVIDIA product briefing, but word is that the new chip is based on 48 ALUs.

G71 has 24 pipes, with 2 ALU's per pipe.  So NVIDIA counts up ALU's as 24 x 2 = 48 ALU's.

The G71 has been manufactured at NVIDIA's latest 90nm fabrication process. Smaller fabrication processes of course offer several advantages. You could add more transistors to the GPU as you have more space to work with, but another nice advantage is a smaller chip design. That means you can use less voltage into the silicon and that saves on heat. Less heat means higher clockspeeds and that's why today's product is clock roughly 100 MHz faster then its predecessor the 7800 GTX 512MB. Did you know that the 256MB version is clocked at 430 MHz? You can smell the performance there huh? Really it's not all about clock for clock performance, but surely it can help :)

Since we are on the topic of the graphics core, inside it there are precisely eight vertex units active. Also the number of pixel pipelines are identical to the 7800 GTX, there are twenty-four of them. Let me enlighten you briefly as to what happens in the pixel pipeline for you to understand its importance. Each pixel that is rendered on your screen goes through a pipe where it'll receive its complex color/effect etc. Each time that pixel is altered it'll pass through the pixel pipeline, one pass is one clock cycle.

The 7900 GTX, actually throughout the Series 7800/7900 line, has has eight ROPs. ROP is short for Raster Operation and a portion of a pipeline, responsible for AA, Blending and Z-Buffer compression. Simply stated a ROP is basically the output engine of a pixel shader pipeline. The pipeline is scalable, each pipe is available at any time in sets of 4, which we call quads.

Of course next to the GPU the most important thing is it's memory to work in. We call this the framebuffer. And the faster it is the higher your memory bandwidth to work in will be. Suffice to say is that the 7900 GTX 512MB is armed with the latest and fastest memory available and a price tag that's just sweet. 499 USD people!

The GeForce 7900 GTX 512MB

GeForce 7900 GT 256 MB a.k.a G71 part deux

Next to this new flagship there's another high-end G71 product, it's called the GeForce 7900 GT and pretty much is the slower version of big daddy GTX. This product has the very same pixel pipelines and vertex processors as the GTX, in fact it's 100% the same chip yet it's clocked significantly slower at 450 MHz and is armed with gDDR3 memory running at 1320 MHz (2x 660 MHz) which also has been brought down from 512MB towards 256 MB. Now if you look at the chart at the top of this page and start comparing a little then you'll notice that it should perform better than the GeForce 7800 GT and perhaps even the 7800 GTX 256MB versions ... for 299 bucks !

The card is producing much less heat due to the lower clocks and a nice side-effect of that is that it's a single slot solution whereas the GTX has the bigger dual slot heatpipe cooler. It's doesn't mean this card is worse or anything judging from it's clock speeds.

In fact I dare to state that this product will offer incredibly much bang for your bucks as it'll cost only 299 USD, and that's a suggested retail price. Within weeks this card might be spotted for 275 USD or even lower. How will it perform ?

Well .. we'll show you for sure in our benchmark runs. You'll be amazed by the performance for money ratio.

The GeForce 7900 GT 256MB