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One-Point-Four-Billion. That's transistors folks.

The chip is codenamed GT200 and it's the successor to NVIDIA's G80 and G92 families. Why the change in naming? The GT stands for "Graphics Tesla" and this is the second generation Graphics Tesla architecture, the first being the G80. The GT200 is launching today in two flavors.

Let's put aside all the important considerations for a moment and bask in the glow of sheer geekdom. Intel's Montecito processor (their dual core Itanium 2) weighs in at over 1.7 billion transistors, but the vast majority of this is L3 cache (over 1.5 billion transistors for 24MB of on die memory). In contrast, the vast majority of the transistors on NVIDIA's GT200 chip are used for compute power. Whether or not NVIDIA has used these transistors well is certainly the most important consideration for consumers, but there's no reason we can't take a second to be in awe of the sheer magnitude of the hardware. This chip is packed full of logic and it is huge.

If the number of transistors wasn't enough to turn this thing into a dinner plate sized bit of hardware, the fact that it's fabbed on a 65nm process definitely puts it over the top. Current CPUs are at 45nm and NVIDIA's major competitor in the GPU market, AMD, has been building 55nm graphics chips for over 7 months now. With so many transistors, choosing not to shrink their manufacturing process doesn't seem to make much sense to us. Smaller fab processes offer not only the potential for faster, cooler chips, but also significantly reduce the cost of the GPU itself. Because manufacturing costs are (after ramping production) on a per wafer basis, the more dies that can be packed onto a single waffer, the less each die costs. It is likely that NVIDIA didn't want to risk any possible delays arising from manufacturing process changes on this cycle, but that seems like a risk that would have been worth taking in this case.

Instead, GT200 is the largest die TSMC has ever fabbed for production. Quite a dubious honor, and I wouldn't expect NVIDIA to really see this as something of which to be proud. Of course, that doesn't mean we can't be impressed with the sheer massiveness of the beast.

And what do we get from all these transistors? Moving up from 690M transistors of the original G80 and 754M transistors in G92 to the 1.4B transistors of GT200 is not a small tweak. One of the major new features is the ability to processes double precision floating point data in hardware (there are 30 64-bit FP units in GT200). The size of the register file for each SP array has been doubled. The promised ability of an SP to process a MAD and a MUL at the same time has been enhanced to work in more cases (G80 was supposedly able to do this, but the number of cases where it worked as advertised were extremely limited). And the number of SPs has increased from 128 on G80 to 240 with GT200. To better understand what all this means, we'll take a closer look at the differences between G80 and GT200, but first, the cards.

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