Well, I wouldn't have asked for, but I remember these issues on my XP machine, after having installed a second hdd.
'HWINFO' showed me, that the machine got hot. So I installed one more fan to cool it down and it worked.
I have used 2 HDDs for many years, one for windows & apps, the other for data. I too noticed when they were put close together screwed into their bay that they did not seem to cool very well, so I have one in its bay, & the other loose so they both have plenty of air round them. The sides are also off the unit allowing for more airflow.
I think my processor only gets warm due to the fact it is up to 100% a considerable amount of the time. In safe mode it is very happy at only about 2-3%. When I ran the repair tool it was very fast & zipped though the repairs, but sadly no improvement.
There is clearly a rogue driver causing havoc here. Cheers Richard