The reason my desktop PC kept crashing!

[Yorkie]

Recently my PC shut down without warning. I rebooted it, and shortly afterwards it did it again, and again. Initially I wondered if it was a bog, or software malfunction, then I remembered that a couple of years ago it became unstable, and on opening up the PC to see if for example a board or memory module had worked loose on he motherboard, I noticed that the CPU heatsink and fan were clogged up with dust. I removed and cleaned the fan and heatsink, re-seated the heatsink with compound, and all was well after than. At the same time, I cleaned out all the ventilation slots and the power supply fan.

Same thing again - the CPU heatsink and fan were solid. As the printer is next to the PC, I'm sure that the dust is fibres liberated from uncoated cheapo copy paper that I usually use in my printer.

If anyone else has an unstable PC it might be worth checking the state of the CPU heatsink/fan, but maybe others forum members do this sort of 'housekeeping' as a matter of course. I'm afraid I'm not so diligent!

The pic shows the state of the heatsink and fan.

Hope that's of interest.

[AlanBeckett]

Mine gradualy gets noisier and slows down - the Motherboard modulated the Processor Clock depending on how hot the Processor is getting.
It's getting pretty noisy again so it's time to muck it out.

Alan

[Skywave]

Oh yes! Based on a number of real headaches with PCs over the years- nearly all of which were due to accumulated debris, etc. - similar to what David has reported - I do make a regular habit of cleaning out the regularly-used ones that are here: about every six months seems adequate.

Al. / Oct. 18, '13 //

[Refugee]

My computer broke down with the same symptoms and it was indeed the heat sink crammed full with dust.
I used exactly the same fix putting it back on with new processor paste when done.

[Aerodyne]

Now you've drawn attention to this problem, David, I checked my home-assembled desktop. It's in a substantial case with large and numerous air grilles and every one seem to be solid with fluff. A vacuum cleaning is obviously called for!
Tony

[Radio Fixer]

Here is a pic of the ASUS app that give temps, fan speeds, and voltages on MOBO.

   

The right pic shows the PC when built in 2011 and the leftt now. Fan sizes are much bigger than your one David, are up too by 100rpm or so.

So due a clean out!

Gary

[Old Sparky]

Could this be the reason my tower PC hasn't crashed since I've been running it with the side panel off (more ventilation!)
It seems difficult to unclip & remove the CPU fan, though it could probably do with a clean, although, as covered in another thread, I will have to either repair or replace the MoBo due to bad electrolytic capacitors.

[ed731pdh]

A classic foul up I've had to work around over the years has been the use of sleeve bearings in the PSU cooling fans. You turn on the computer and they start to howl. Easy enough fix, peel back the manf label to reveal the sealing plug, pop open and add a few drops of oil to the bearing shaft and all is ok. The pain is getting the fan out of the PSU in the first place, plus the heat coming off the PSU evaporates the oil quite quickly so its usually a one a year job. I now buy PSUs with proper ball races in the fans.

[Nick]

This is probably the most common cause of PCs crashing - overheating. We've covered this in other threads...

A decent quality 1" paint brush with the hoover nozzle nearby is the best way (with the PC unplugged) - the dust is basically human and animal debris & a whole bunch of dust mites - if you are allergic to dust mites (I am!) then keep the nozzle of the hoover close to the brush as you clean.

An air compressor is excellent for getting to difficult places, but DO THIS OUTSIDE else your office/workshop will just have all that nasty stuff just re-distributed... Compressed air is ideal for cleaning up inside fans - rotate the fans by fingertip - if you feel that there is even the slightest "stickyness" after cleaning, replace the fan ASAP with a good quality ball bearing (not sleeved) one.

One point that is often missed is to clean through the PSU - its a classic dust-trap, and should be thoroughly cleaned out too... as has been pointed out by others, the PSU has capacitors charged up to about 400V, so if opening up the PSU case, leave it well alone for 10 minutes after unplugging before cleaning. Note that even when a PC is turned off and no fans are running, the PSU is still providing 5V standby power to the motherboard and is thus still a danger.

If you must remove the CPU heatsink to clean it (not always necessary), then please note that you shouldn't reuse the old thermal compound as it dries out over time and is never so good second time round when trying to re-seat a heatsink.

Important point here too - the stuff that's generally used is silver-loaded and is conductive, i.e. bad news if not where it's supposed to be, so clean it off very carefully with IPA (not the beer, Isopropyl alcohol aka 2-propanol) and a cotton bud, being VERY careful not to get any on the PCB or on other components - only use IPA in well-ventilated areas - you will get a blinding headache otherwise! Been there, done that, got the headache Whilst IPA is best, methylated spirits is OK too...

EDIT: Should have mentioned that sometimes a thin thermally conductive rubber pad is used. If there was one there, don't re-use it (they don't reform well). Remove it carefully with a craft knife, clean with IPA, and proceed with using Ag-loaded compound as below...

Important: If you remove the CPU chip itself from its socket, either deliberately or accidentally, do not handle it without an anti-static strap round your wrist that is properly earthed (not to the PC case as that is unplugged, hopefully!)

Its important to use the same sort of Ag-loaded compound (sometimes called "Arctic Silver") to re-seat the heatsink - use extremely sparingly - the thinnest possible coat that completely covers the metal part of top of the CPU chip (actually, stopping maybe 0.5mm - 1mm short of the edge is good) and absolutely no extra that might "splodge"/squeeze over the edge when clamped - a thin bit of flexible plastic used as a spatula is excellent for this.

Put a sticker on the back of the case saying when it was last cleaned out (I do this for batteries in smoke alarms & test equipment too).

Lastly, think about where you site your PC - if its on a carpeted floor it will collect a whole bunch of rubbish - just raising it off the floor by 4 or 5 inches can really help.

[Radio Fixer]

All good stuff Nick and to be reminded of. I have always built my own PC's s so knew it but its easy to get lazy and just let it soldier on: "if it aint broke etc". This PC has a 6 core chip with a huge non chip maker supplied HS and fan + a large speed controlled back fan. I never use a case supplied PSU either but buy a superior rated one again with temp controlled fan, hopefully with better bearings, never had one screech yet!

Most of the time its ticking over and I only see the 6 cores in use when video rendering etc.

Gary