I have been suffering from really bad and inconsistent I/O performance for a couple of weeks. Shortly after booting, the speed reported by HD Tune was perfectly fine. I forgot to close HD Tune again. Now it displays a notification that my hard disk temperature is critical. I did another speed test, the transfer rate was in the single digits for most of the disk.
It looks like the performance issue is caused by overheating. Is this plausible?
(Of course I know that even if this is not the case, I need to do something about the overheating.)