TheInquirer reports that Nvidia G80 should be seen the face of the planet in late Q3 or early Q4. It could be ready for the end of Q3 but only if the first tape out goes well.

We still cannot confirm the status of the G80's tape out - if it's going well, September. If not you can easily add an additional two months to the projected date.

The chip will be DirectX 10 compliant of course but it won't have the full implementation of Shader Model 4.0. It won't do the unified Shader but it will be Vista ready. Most of the chips out today are Vista ready at least the high end ones. This chip has every chance to end up faster than ATI's upcoming R580+ fall refresh chip but this one will get R600 beast to compete with. It is still too early for clocks and final specs but we will start digging this one.