PC switches itself off.

WhiteChristmas

Ratboy wrote: »

I recently learned that any aerosol, if you hold them upside down they blow air...but not tried it.

Not quite. They'll blow their propellant, which may well be flammable (LPGs are quite common as a replacement for the old CFCs - have a look on your deodorant can). There are plenty of potential sources of ignition inside electrical items; I wouldn't go spraying random aerosols inside my computer!

Also, it's extremely likely that the spray in those circumstances will contain some (even if only a tiny amount) of the other contents of the can. I don't think your fans would thank you for a coating of hairspray!

cookie365

Get one of these things for cleaning dust out of your PC:
http://www.amazon.co.uk/Giottos-GTAA1900-Rocket-Air-Blower/dp/B00017LSPI

But ... if the computer or the CPU was overheating I'd expect the BIOS to start bleeping away at least for a few seconds before it switches off. Unless it doesn't have an internal speaker.

Try installing something like HW Monitor to keep an eye on temperatures.
http://www.cpuid.com/softwares/hwmonitor.html

Speedfan is similar - less friendly to use, but allows you to store logs and set email alerts and stuff like that
http://www.almico.com/speedfan.php

victor2

As everyone else is suggesting, it sounds like overheating.
I saw that same problem on a system and it turned out to be the CPU cooling fan that had failed. That particular motherboard had a heatsink on the CPU and small fan on top of that. A replacement was easy to find and only a few pounds - it's been fine ever since.

techno12

Agree with consensus.

I had this exact issue the other week, the computer would instantly power off as if someone had yanked out the power cord.

Using

http://www.cpuid.com/downloads/hwmonitor/1.23-setup.exe

revealed that the CPU temp was at 85 deg c, and would never waver. This is the max displayable on my particular machine (ie it was greater than this, but the BIOS limits the temp displayed to 85).

Easy to fix - the CPU heatsink fins had loads of fluff between and on top of them, blocking the air flow from the fan above. I just used a plastic pen (a BIC) to scrape this off.

CPU temps now 55-65 deg c range and haven't had a random switchoff since.

(I initially thought it might be the PSU as its fan wasn't spinning, but apparently this is normal behaviour and the fan only comes on as and when)

Cycrow

macman wrote: »

Using a vacuum cleaner inside a PC any anywhere near the circuit boards is a bad idea-it produces large amounts of static.

its not actually as bad as alot of people think. PC components are not as fragile as some people seem to beleive, they are actually quite robust and its quite difficult to damage them due to static.

althou, vacuums are not the best thing to be using, as you want to blow out the dust instead