Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I watched several videos on YouTube, went through a lot of overclocking forums and websites, but I am yet to find a "correct" answer to this question.

Some agree with the "pea method" where you apply a pea-sized glob onto the center of the CPU and then mount the heat sink over it and let the pressure of the sink spread the thermal grease evenly across the surface.

Others tend to gravitate towards the "business card method" of evenly spreading a thin layer of thermal compound across the CPU surface using a business card.

And then I read something about needing to apply more thermal compound to laptop CPUs because they don't have integrated heat spreaders.

I'm confused. I own a Acer 5542G notebook with an AMD Turion II X2 M500 CPU and ATI Mobility Radeon HD 4570 GPU. This computer has been overheating a lot lately (even playing Minecraft for a few minutes would trigger a system shutdown) and I just recently took it apart and cleaned it.

There was no dust accumulating on the fan grill, so I removed the thermal compound, cleaned the CPU surface and applied some new compound. I used the "pea method". My CPU has a rectangular surface so I applied two little pea-sized dots.

Where I used the thermal compound

After I did this, I ran CoreTemp and here's what I saw (idling temperatures): CPU running super hot!

That's a lot of heat! I'm guessing I screwed with my application of the thermal paste. I'm hoping anyone who owns an Aspire 5542G or a computer with an AMD Turion X2 M500 processor that has experienced the same problem could help me out here. Thank you.

share|improve this question
    
i do the credit card option, i dunno. Personally that pea sized amount doesn't look nearly enough for my liking. I generally put a layer as thin as i can, but across the whole die edge to edge. –  Sirex Sep 29 '13 at 21:23
    
Does your notebook have an AMD CPU? Could you tell me what idling temperatures you get before and after you've applied the thermal grease? –  Vinayak Sep 29 '13 at 21:32
1  
yeah, i should state that spreading thermal paste is one of those topics which gets way more discussion that it needs. In my experience at least, sky high temps has never once been solved by one pasting technique over anouther. –  Sirex Sep 30 '13 at 1:43
1  
Correctly re-attaching the heat sink on a typical laptop CPU is very complex. The heat pipes must not be bent, even a tiny bit, and the screws must be tightened in the correct order and to the correct tension. I would recommend letting a professional do it. –  David Schwartz Oct 1 '13 at 7:13
1  
One other note -- despite being supposedly designed for the purpose, even the best "gaming" laptops should be run on an active cooling pad (that's one with fans) which will help substantially with keeping it at reasonable temps. Also if you mean that you checked the heatsink fins for dust, but you haven't checked all the air vents (ridiculously on the bottom most of the time) please also do the latter to ensure that air is blowing out of them. –  Debra Oct 1 '13 at 12:23
show 4 more comments

2 Answers 2

up vote 1 down vote accepted

Use a thin layer on very clean surfaces (alcohol is fine for cleaning, but let it dry before proceding). The thermal paste does not dissipate heat; its purpose is to put the CPU in close contact with the heatsink, so that the heat from the CPU transfers to the heatsink. So a thinner layer actually will work better & create a better seal between the two pieces of metal. The "pea", however, has to be put under great pressure to spread across the surface, and is less likely to keep the entire surface in good contact.

Also you might go for a better-quality paste, which can make a big difference. Thermal paste is something I never mess with going the cheapest, as even the "good stuff" is still usually around $10 or less (without using all $10 worth in one shot, too.)

If it is running too hot, it may mean that the CPU & sink are just not tightly enough meeting. You can often tell when you take it apart, too, because if the CPU lifts right off, there isn't much of a seal. Oddly enough, if the CPU is hard to get off, that usually indicates a better seal.

share|improve this answer
add comment

As Debra and Sirex suggested, I decided to go with the "business card" method of application of thermal grease and this is what my CPU and GPU look like now:

Viscous thermal paste applied to CPU and GPU using "business card" method

After I reapplied the thermal grease, my computer's idling temperature dropped by almost 20 degrees and even under high load (I used Prime 95 for CPU stress testing) it wouldn't cross 90 degrees.

CoreTemp generated CPU temperature graph

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.