Nvidias GF100 reports to the user as GF100b
The GF100 GPU solves some issues that the GF100 had. Critics won't accept its higher model number and consider it more of a GF100b. Nvidia's very own BIOS-flashing tool now reveals that those critics and the makers behind the chip had the same idea.
For the sake of flashing a BIOS to a graphics card, PC Games Hardware doesn't shy away from using archaic user interfaces. In order to do so, Nvidia users are forced to use DOS-based tools like Nvflash or programs made by the PCB-designers. When we tried to modify the BIOS of a Geforce GTX 580 graphics card, we made quite a discovery: The tool doesn't enlist a GF110 but a GF100b. The latter is, according to Nvidia, no GF100. Every single transistor had been inspected and revised. It turned out to become the GF110, right now at stepping A1, which is pin-compatible with the GF100 chip.
FYI: The GF100 without suffix stems from one of the first chip revisions; to be precise, this one is used on every GTX 480 / 470 / 465 at A3-stepping. Ever since, chips with the b-postfix have been fundamentally revised or shrinked GPUs. For example there was the GT200b (GTX 285 / 275) which was a GT200 shrinked from 65 nanometers to 55 nanometers.
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