The GeForce 8600 will use the same PCB as the GeForce 7600, which in turn used the same PCB as the GeForce 6600, DailyTech reports. Just like the G73 the G84 and G86 GPUs will be pin-compatible with the old NV40.
The GeForce 7600 and 7300 became readily-available, affordable video cards almost overnight. A major secret to the success of these cards was due to the fact that the GPUs were designed to use the old PCB designs from GeForce 6200 and 6600. Once again, NVIDIA will take advantage of this mentality again with the next generation G86 and G84 video cards scheduled for release this quarter.
G86 and G84 (G8x family) GPUs do have some major differences between G73 however. For starters, the main G73 power rails run at 2.5V -- on the G84/G86 these rails run at 1.2V and 1.8V. The G73 clock generator runs at 1.3V while the G8x family clock generator runs at 3.3V. Additional dead pins have also been allocated on the G8x family for higher density memory.
A special thing about the G8x family is the support for more than four GPUs, at least in the design. This would allow some physics project in the future.