Nvidia G80 has problems - SLI and HDCP broken for now
 

What is broken? Well, it seems G80 has a lot broken, some that will be fixed before launch, and some may be harder to fix.

Drivers on the 25th October will fix SLI, as we understand it is pretty badly borked in the current release. How badly? Enough to crash almost every time, said one source, and so basically unusable.