CPU overheating after cleaning it

Question

I wanted to clean my computer CPU heatsink and fan itself, because the temperature is not what I wanted. About (50C ~ 70C). I have Intel Core 2 Duo E4300 @1.8 GHz (LGA775).

The heatsink wasn't so scary filled with dust but I wanted to clean it anyway. I didn't know how to get heatsink with fan from the socket. So after 25 minutes I've figured it out. But I didn't know how to get it back on so I spent a lot time getting out the motherboard from the case.

The fan and heatsink... The case and all components are clear of dust. (I'm tired now). Then I put all back just the way it was, well did few things on cable management. But the problem was that I didn't know how to connect front audio connectors. I had Windows XP hibernated. So I started the PC and everything was normal, except CMOS memory was clear. I configured the BIOS just the way it was and while I was doing that I saw about 58C CPU temperature and fan at 1789 RPM. Restarted the computer with new settings applied. But Windows halted with Blue Screen (I forgot what error it was but something with KERNEL).

Restarted the PC and deleted hibernation session and everything was back normal. But couldn't record any sound from front panel microphone. The problem was that I messed ground wire with mic. Again after fixing it I turned computer on. No problems. The fan currently is noisy and temperature was 78C. The temperature before was 55C - 60C at idle. Now it's about 60C. If I do something then temperature raises to 79C. While speaking in skype the temperature was 82C.

Could this problem occur because of the thermal grease (it's old and never replaced)?

Edit
The problem wasn't in thermal paste (because I didn't touch it). The problem was that I installed heatsink wrong. Now instead of regular 60C CPU temperature the CPU is at 48C (cool).

Solution 1

Yes, it could be the thermal paste, or even not quite a flush mount. I would suggest picking up some new thermal paste from either an online resource like Newegg, or from a local retailer like Fry's or Microcenter and follow the instructions provided with the product closely. Additionally, make certain the heat sink is flush, and mounted firmly with all 4 pegs. If even one is loose, the gap created could cause the problem you are having.

Solution 2

Just my approach to clean CPU fan from dust.

1. Turn off the PC

2. Disconnect CPU fan

3. Turn on the vacuum cleaner

4. Put sucking end of vacuum cleaner tube near the inlet of the CPU fan

5. Allow CPU fan to spin in reverse for a while and go few rounds to pick up dust from all parts of the fan and radiator underneath

Works perfectly with Intel Core Duo fans. Does not require removing CPU, applying grease nor triple checking if fan sits tight.

I know this is not real answer but piece of advice for the next time.

Comments

[uxout]

Are you sure you have the heatsink mounted securely? If it's on tight, you should be able to tug and the motherboard should move with it before the heatsink comes off.

[Little Helper]

@Shinrai I don't get you. Sorry..

[HikeMike]

So you are reusing the thermal paste you applied a long time ago instead of clueing the components and applying it anew?

[uxout]

@Roberts - You removed the heatsink. Are you sure you put it back on properly? If it's loose, the processor will run very hot.

[uxout]

@DanielBeck - Assuming those pictures of the heatsink are the one in question, this is stock Intel which has preapplied thermal pads on the bottom of the sink. (You can see them in the picture). I have no idea how well these hold up over time but they always come off cleanly so I can't think it would be a huge problem.

[Little Helper]

@Shinrai I spinned it around - 180°

[Dan Is Fiddling By Firelight]

@Shinrai Intel's current heatsink uses pre-applied thermal grease; not a pad like they did in years past. I believe the same is true of current AMD heatsinks; but I haven't bought one recently so I'm just going off internet images.

[uxout]

@DanNeely - I don't know what heatsinks you've been looking at, but the ones that I see daily coming with LGA1155 chips have a pad. (Specifically three small semi-rectangular pads, exactly as in the picture).

[Dan Is Fiddling By Firelight]

@Shinrai That's the same pattern (and color) as on the heatsinks I've gotten with LGA1366 chips, and they wiped off just like a smear of arctic silver would. They didn't require being soaked in acetone and scraped off with a razor blade like the old pink pads from a decade ago. Nor were they the thick, non-spreadable material placed on the ram chips in the ATI-5870 card I replaced the cooler on last summer.

[uxout]

@DanNeely - Okay, this is clearly just a difference in terminology for us. You're right in that they're nothing like the pads of old, but in my experience they tend to scrape off in a single piece, don't leave huge smears after they've been installed, and they're not the same consistency as I'd expect from a decent quality thermal paste out of a tube either, so I consider them 'pads'. They are still a far cry from those horrid old pink things, though.

[Dan Is Fiddling By Firelight]

@Shinrai When new I remember them wiping off in a smear like grease. I never used them so I'm not sure what their used consistency was. I wonder if Intel's used more than gray tim in the last few years.

[James Broadhead]

beat me to it :) Be quite careful when you're removing the intel fan (pictured). It is held in place with screw keys that are disengaged by turning them 90 degrees, and the plastic connectors beneath the motherboard are quite easy to bend/break if forced (which will allow the black 'plugs' in the motherboard to come free).

[James Broadhead]

I have found that these models of heatsinks (since core2) have been quite adequate at keeping my chip cool. The days of stock heatsinks being insufficient during the Pentium4 days are past :)

[Paperlantern]

How do you know what his satisfaction is. Stock heat sink / Fans are designed to cool the processor adequately under all loads, per manufacturer's specs. Aftermarket ones are for people overclocking and doing very heavy CPU intensive work. Stock CPU coolers are like all weather/all season tires, perfect for the everyday driver. There are other tires for enthusiasts. Aftermarket coolers are for enthusiasts.

[chmod]

@ James Broadhead, please don't get me wrong, I didn't say that stock cooler provide insufficient cooling but just not to "your satisfaction" For example with stock cooler, the idle temp is around 40-50C. Which is OK for the CPU. But with better cooler, your idle temp could be around 25-30C. I just feel happier to see my CPU run cooler. That's all.

[uxout]

+1. Based on the question, I don't think it's attached properly.

[uxout]

Agreed with the comments - these heatsinks work fine for 95% of users.

[Ramhound]

It sounds like the author tried to use the same thermal cooling pad. Once the removed from the cpu, the pad as to be replaced, you can purcase replacement thermal cooling pads or thermal paste.

[Paperlantern]

If you cleaned the dust out, but didnt touch the paste/pad that was there, most certainly this is part of the problem. Proper reinstallation of CPU/Heatsink/Fan requires cleaning the old compound off of the CPU AND the heatsink so both are clean metal again. Typically 100% Isopropyl alcohol, or equivalent cleaning pads/swabs should be used for this. Lesser solutions such as those found in first aid kits or medicine cabinets have impurities that can damage electronics because they are a solution less than 100%. Once clean, apply new, fresh pad or paste according to its instructions.

[Dan Is Fiddling By Firelight]

@Paperlantern Anyone selling you something higher than ~90% isopropanol is ripping you off. Once the bottle is opened it draws moisture out of the air until it's only ~90% pure.

[Paperlantern]

@DanNeely Sorry Dan, this is what I was taught, and learned to pass the A+, and have so practiced for many years since. If it has changed then so be it, but I always use 100%, if it ENDS UP BEING 90% after opening, then, that's just how it goes, still better than 70%.