How to correctly apply Thermal Paste?

[hardys77]

Hello. My Cpu is overheating and I bought a thermal paste, sadly the only one they had was DeepCool Z5, it's sunday so I rushed a little because I really need my PC. I saw some videos on youtube that show that you only need to put a little bit, but on the back on the thermal paste it says to apply a little bit and spread it all over the CPU. Which is the correct way to apply it? thank you.

 

[ex_bubblehead]

Place a rice grain size bead in the middle of the cpu, place the cooler, and while pressing straight down twist slightly back and forth to spread. Then lock it down. Do NOT remove the heatsink to check the paste or you will have to clean it off and start over (you will introduce air bubbles).

 

[hardys77]

Place a rice grain size bead in the middle of the cpu, place the cooler, and while pressing straight down twist slightly back and forth to spread. Then lock it down. Do NOT remove the heatsink to check the paste or you will have to clean it off and start over (you will introduce air bubbles).

I got a plastic thing looking like a flat spoon to spread it all over. Should I use it or nay?

 

[Solandri]

It's usually enough just to put a rice-sized (or half-pea sized) dab in the middle. Squishing it down with the heatsink will spread it out for you. You do NOT want a layer of paste between the heatsink and CPU like a layer of mayonnaise. Most of the heat transfer is between metal-on-metal contact between the CPU and heatsink, so the two have to be touching each other. I squish it down by slightly twisting it until I feel metal grinding on metal. Then I strap it down.

The thermal paste manufacturers tell you to use a lot because they want you to use it up more quickly. Then they can sell you more paste. The only purpose of the paste is to fill in microscopic air gaps between the two surfaces (which aren't perfectly smooth), so a little goes a long way. Air is about 100x worse at conducting heat than thermal paste. And thermal paste is about 100x worse at conducting heat than metal-on-metal contact. So a thick layer of paste is actually worse than no paste.

 

[hardys77]

I don't have rice. I applied a little thermal paste and covered the cpu (not all) just in the middle. Sadly, the same temps on the cpu. 50-60C in idle... I guess it's time to get a new cooler then. I didn't apply too much paste but not to less.. anyways. Thanks for you answers.

 

[hardys77]

Update: I usually test the cpu by playing GTA V to see how hot the CPU gets. Before applying thermal paste would go up to 100+ C degrees. Now it goes up to 86C and stops there. I have to replace the cooler,right?