i need to ask a computer related question.

background:
i need some help resolving a problem i've been having for months that i've tried to resolve without success. around easter i went on vacation for a week or so, only to come back to a computer that would restart out of nowhere. it got gradually worse. at first, it seemed random at first. now, whenever i do something stressful to my computer (and sometimes things that are not stressful) it just locks completely.

*please note: i can change the way the computer acts by checking "automatically restart". if this is checked, when the system fails for whatever reason this is happening, it will just restart. if it isn't checked, the computer completely locks indefinitely*

things i've noticed and suspected:
i noticed that whenever i'd play a game that would stress my computer, it would lock so i suspected the graphics card. however, switching it out with another did not fix this. then i went into my bios's hardware monitor, and i could clearly see my cpu temperature rising steadily. so i went and applied more thermal gel, cleaned the fan and the heatsink out, and applied a box fan to the side of my case to try and keep the temp down. after this, it still did not fix my problem. to this day, i suspect either the mobo for giving false readings, or the cpu being shorted. (that happens sometimes, doesn't it?)

solutions i've tried:
switching ram (that was the first hunch i had, however both sticks of ram are good)
switching power supplies
applying new thermal paste to my cpu
switching hard drives
using new cables

solutions i haven't tried:
switching cpu
switching mobo

for educational purposes, i will list:
things i can run without freezing (all the time):
internet explorer (froze once or twice)
mozilla (froze once, just today)
nnnesterJ - nes emulator
cuteftp
winamp
photoshop (only froze one time ever)
macromedia flash (froze once)
aim
visualboy advance - gba emulator (froze a few times)
snes9x - snes emulator
fruityloops studio producer (froze when rendering a song)

things i definitely can't run:
counter-strike
battlefield 1942
zsnes - snes emulator
hitman 2
bomberman online
mame32k - arcade emulator
anything that trys to render a video for more than a minute or so

basically, when i hear my harddrive start to spin up, and it spins for about a minute and a half, it will all of a sudden lock and the hard drive will stop spinning. however, the hard drive seems to not be the problem, considering i've switched hard drives 3 times to try and fix the problem, and i've switched the cables also.

to avoid the problem, i've just been chatting, posting on forums, messing around in flash, photoshop, and fruityloops, and playing emulators. of course, i own all the games i have as roms.

can anyone provide a possible solution outside of switching my mobo or cpu? although that may be the culprit, i'll have to wait to attempt something like that.

Edit:

i suppose computer specs would help: shuttle av41p (mobo) 2.6ghz p4 500fsb (cpu) /w stock intel cpu fan+hsink 1.5gb pc2100 ddr (ram) 80gb maxtor (hd) radeon9200 se (vid card)

Sounds like definite overheating. Add case fans.

What kind of power supply are you using? You already said you tried a different one, but I'm still curious.

Now, for a few easy cooling solutions. Make sure your wires are tightly binded and out of the way. Maybe cut a blowhole in the top of your case. Oh, and install yourself some more fans like your boyfriend Grav said.

would a fucked up cpu overheat even if adequate cooling was added?

How much cooling? You shouldn't need more than a few fase cans and the stock CPU fan.

You might need to get some Arctic Silver 3 to put between the heatsink and CPU..

How much cooling? You shouldn't need more than a few fase cans and the stock CPU fan. You might need to get some Arctic Silver 3 to put between the heatsink and CPU..

i just recently dumped a new packet of thermal paste and cleaned out the heatsink and fan, so they're running optimally. that seemed to keep the temperature down a bit. i have the side of the case open and the back of the case has empty holes where the pci slots are, so i have a big box fan blowing air into it and the air is certainly circulating. please note that it is very cool in my house, as the air condtioning is on. i definitely don't think it has to do with air circulation as much as cpu corruption.

i have a shuttle av41p, by the way.

Then it's possible that

A) Your motherboard has broken transistors or snapped off capacitors.

B) Your CPU is on crack.

C) You're a liar, and need to die.

What kind of Motherboard do you have? There have been cases of bad caps on Motherboards about a year or so ago. Check the caps and make sure they aren't bent out of shape or deformed.

Case fans didn't help me. I got a 6000 RPM uber-CPU-fan. Still, I'm running faster than I should be, so I suspect a short in the processor. Yes, that can happen.

I'll bet if you replaced your processor, that would fix your entire problem.

Anyhow, the problems you're experiencing are almost exactly what I had. My computer restarted (very rarely) by itself. It got worse over time. I had a hard time booting up sometimes. Eventually, it wouldn't make it to Windows when booting. It would just shut itself off during the boot process.

I tried different cables. I tried a different video card. I tried swapping ram. I bought a new power supply. I bought a new mobo. Finally, a big motherfucking CPU fan fixed the problem. I kept all the gear though. It was all a nice upgrade over what I had.

Sounds a lot like what my pc did.

My powersupply was faulty and it stopped working(slowly stopped) without any indication anything was really wrong. PC kept freezing and restarting. Took it in under warrenty, replaced power supply and now it works just like new.

* The thing just didn't shut off or anything, it rebooted to windows, shut down and such after time. I couldn't run anything. GL though.

He already said it wasn't the power supply

Before you replace the proc take it out and try it in a friends PC that is working. See what happens. Your 2.6 is still plenty fast so no need to upgrade if you don't need to.

pretty sure none of my friends have a socket 478 mobo, so is there a way for a local computer company to be able to test my processor?

You might could get someone at Fry's to do it for you, but they'd charge ya $10 or $15. I say might because they'll test mobo/cpus you buy there for a fee, but... you already own this CPU. Anyhow, I'd just go ahead and get the new CPU fan. Even if your CPU is broken and needs to be replaced, a big, badass CPU fan is always worth the money.