ace1 . . . it could he beat, I wouldn't rule it out.
But the fact that a format fixed it for a while leads me to suspect it's more likely to be malware.
Bigger fans do help with heat problems, as do more efficient or more numerous ones.
The programs to control fan speed don't work with all motherboards and fans, unfortunately.
Great for those it works with.
More air flow helps keep the components cooler, you're right there.
And allocating more virtual memory rarely helps, unless it's set very low.
Maxing it out is also, I think, not the best thing you can do.
I recommend setting it to about twice or 2.5 times your real RAM, and setting min. and max. paging file size to that value.
This prevents it getting fragmented whilst in use, and stops Windows sucking performance managing it all.
It's rarely used if you have 1Gb of RAM or more anyway, unless you run a lot of memory-hungry applications.
All this is beside the point though, unless it does turn out to be a heat or virtual memory problem.
An interesting contribution nonetheless, thanks for your input.