Laptop Problem(s)

I got a hand me down laptop from my step sister, Im guessing its a couple years old (Toshiba Satellite A30), worked fine for what I used it for.

After a couple weeks of random usage, it started... acting up. Turns off suddenly, and it tries to reboot, but before the monitor can even load up BIOS, shuts down repeatedly. Again and again. I can't even turn it off manually, I have to remove the battery to stop it doing the cycle of turn on, boot down, etc. I dont think it could be overheating because I can leave it off for days at a time, boot it up, and crash within 20 seconds. No way it heats up THAT fast.

This happens so frequent now that I can never get to the login screen for XP without it rebooting, so I tried reformatting it... it would almost finish every time before shutting down at the set up time zone/etc screen.

(note, when the reboot cycle begins, it is almost impossible to go into BIOS)

Should I just junk it? Or is there just something I'm doing wrong but being an idiot about?

edit: some stuff

Also, I've been getting random blue screen errors that lock my computer up and force a restart on my end, causing the boot on/boot of cycle to start.

Here's the error typed word for word:

"A problem has been detected and Windows has been shut down to prevent damage to your computer.

IRQL_NOT_LESS_OR_EQUAL

If this is the first time, yadda yadda yadda ... etc

Technical Information: (blank)
"

it might not be overheating per se, but it could be damage to the motherboard or other parts resulting from previous overheats.

I have the same laptop, and its doing the same to me. Check the fans as it is booting or try setting a box fan under it to cool it. You may have to get the fans checked or the mobo even. Good luck with it