Yeah heat has always been an issue with nvidia over the last couple of generations but the gtx 460 produced little to no heat with gigabytes HSF. What is rather sad is the fact that Nvidia has no official response to the lockup issue, which dates back to August for some poor folks. Nvidia dropped the ball with the 8800 gt overheating, teamed up with HP on some overheating laptops and now this. Furthermore, the lockup issue is not isolated to just the gtx 460, 470, or 480, since some people with 500 series cards are having problems.
I still enjoy Nvidia cards but their customer support in regards to this issue has been an abysmal failure.