heya
I'm gonna run a memory test in a sec.

And yes, I think the problem is that my CPU is overheating.
However, sometimes, when it's not overheating (or shouldn't be - this
is literally 10 minutes after its been turned on) some programs still
lag, and it doesn't get any better.
I didn't have any viruses or spyware/adware last time I checked (about
a week ago) and I had the same problem before that checkup.

I'll get back to you after the memtest.

(Just another thing... Could it be because my CPU is running at 133Mhz
clock speed?)