[mng2]

When I talked to somebody at Blue Waters (petascale supercomputer at UIUC), she told me that they had uncorrectable errors once or twice per day, even with ECC. Blue Waters has 22640 compute nodes that contain 16 cores each (we'll ignore the GPU nodes). So even if your typical home computer had 16 cores, you would expect 12 hours * 22640 = 31 years between uncorrectable errors.

Caveats: most computers don't have ECC, and I don't remember if Blue Waters was completely installed when I visited.