The GeForce 7800 GTX 512 MB-the new king of 3D? (page 1: GeForce 7800 GTX 512 MB)

Determined not to be surpassed by ATI, NVIDIA has quickly reacted with the release of the GeForce 7800 GTX 512 MB, a new card based on their latest high-end GPU. The name of this card can be quite misleading as it isn´t just a 7800 GTX equipped with 512 MB of memory, it’s much more.

A super-powered GeForce 7800 GTX

Because of the lack of competition during the GeForce 7800’s release,

NVIDIA didn´t have to come out with a very high-end product. So, it kept this "Ultra" on the sidelines for a possible later release. You may notice we put ultra in quotation marks, because NVIDIA has decided not to use this suffix anymore, the new one being exclusively GTX. It’s been used since June, however, so what will NVIDIA call this new model? 7850 GTX? 7900 GTX? NVIDIA has decided upon 7800 GTX. According to the manufacturer, this ultra model will be equipped with 512 MB and the standard with 256 MB. This is how they will be differentiated, but we find this unfortunate, because it’s hard to tell them apart.

This is true all the more that differences between the 256 and 512 MB versions are relatively significant. The GPU is clocked at 550 MHz instead of 430 (28% increase) and memory at 850 MHz instead of 600 MHz (a more 40% gain in memory bandwidth). These characteristics only lead us to believe that there should be consequent performance differences between the two cards and that they should have different names.

To work at such frequencies, the GPU needed a very efficient cooling system. NVIDIA chose the monster that you have probably already seen on the Quadro FX 4500 or Leadtek´s GeForce 7800 GTX. This massive cooling system includes a copper base and four heatpipes connected to blades that are cooled by a central fan. It’s very silent and efficient, and while the fan rarely spins at maximum speed it remains very discreet.

So if the PCB of the 7800 GTX 256 MB was designed to include 512 MB, the 512 MB version uses another one (is this clear?). Its PCB was improved to facilitate frequency increases and adapted to 512 Mbit chips, which as their name indicates are double density compared to the 256 Mbits chips in the GeForce 7800 GTX 256 MB. There are only 8 instead of 16. This is probably more interesting in terms of fabrication costs, but it also enables this chip to function at very high frequencies. NVIDIA uses the latest revised Samsung 1.1 ns GDDR3 chips, which are capable in theory of working at 900 MHz!