Bit-Tech published an Nvidia nForce 680i SLI lab update where they test the latest P30 BIOS

There's no doubt that if you want ultimate compatibility for the latest processors and 1333MHz FSB then the latest P30 BIOS is a de-facto upgrade. However, it's disappointing that the performance hasn't shown itself to match the claims in virtually every single test. We used the exact same drivers and hardware on both machines so they are as directly comparable as possible, the only difference is the re-branding, however the fundamental board underneath is still the same.

It's not as if it was limited to one board either, we had two in from EVGA and XFX and both offered the same out the box, so we are pretty certain it's not a "bad flash" or "bad board". To be perfectly honest, despite the late success with quad-core overclocking, we've had sporadic troubles with this BIOS on both boards.

Nvidia nForce 680i SLI Lab Update with P30 BIOS