Comment 51 for bug 270798

I had this exact issue on a Dell Precision M6300. With no apparent reason, the computer just freezes. Depending on what I'm doing the uptime before the freeze is between 1 and 3 hours. I tried all the things proposed here, but nothing worked. I also tried to disabled the BIOS settings for virtulization extensions but it did not solved the issue. I also disabled the acpi system but the system still freezes.

I have the feeling that the freeze happens when the cooling system is supposed to be started up or shut down, but it's just an impression.

I tried with debian testing and the new ubuntu 9.10 beta, but the problem is still there.

I could speed up the freeze by running glxgears and open a few flash videos in firefox. It's a matter of 10-20 minutes before it hangs.

All this tests were done with 64bit distributions/kernels. Yesterday I installed an ubuntu 9.10 32bit and the computer has been running for a few hours without freezing.

Hope it helps.

Alfonso