I’ve got an audio editing system running windows xp, it’s quite old (about 5 years), and has taken to crashing regularly. No bugs on there, AV all up to date, data backed up to external drives, but even on simple tasks it keeps conking out. What could it be?

Any symptoms or does it just turn itself off?

Drive or fan failing? I’d start with a fan.
Boot virus check would be good, too.

it just turns itself off. No warning. Fan seems fine, drive whirrs until the reset.

Sounds like overheating, is it a Laptop or workstation?

workstation.

just cleaned the vents to see if it makes a difference

I had a faulty power switch on my PC (well, rubbish soldering, that meant one wire was intermittently connected).
It would occasionally just turn off without warning. Could be that….

Or as suggested…overheating? To rule this out, you could open the side and run a desktop fan into it? I did this at uni with a PC that used to overheat, but I didn’t have time to sort it out due to an impending deadline.

disc cleanup worked, now defragging. It’s even these little processes that keep killing it. LEt’s see what happens

If you’ve got the side off the case, check that the heatsink is still firmly attached.

Only happening when using specific software?

What do the event logs display whenever this happens?

What brand PC? some brands have “intelligent” monitoring which may notice overheating or similar