Replacing CPU Fan


Thread Starter
Feb 18, 2009
Hi everybody :
First...........I'm running Windows 7 Pro 32-bit, 3GB RAM, 500Gb Hard Drive. My question is about replacing the CPU Fan. I recently replaced the CPU Fan (it was pre-pasted). My concern is ............AFTER installing the fan, should I wait for the thermal paste to "set" before runing on the computer ? Or is it okay, directly after installing the fan, to turn on the computer ?
Aug 8, 2008
FTER installing the fan, should I wait for the thermal paste to "set" thermal paste designed to be free flowing or flexing. So your good to start up the PC.

Note; depending on system IMO the thermal paste should be reapplied every 5 years. This is due to the heat drying out the thermal paste. Over time it (thermal paste) losses it's effectiveness. Always buy a high quality thermal paste. I'm partial to Artic Silver brand.


Jan 2, 2001
From the description in your post, I am assuming you are replacing the heatsink fan and not just the fan. If it is just the fan, no thermal compound is used.

What happens when you apply new compound OR use a heatsink fan with pre-applied compound is that on the initial pw ON the compound flows into the VERY small peaks and valleys between the processor and the heatsink fan base. If the two parts [cooler and processor] were perfectly machined, there would be no need for thermal compound. The cost to machine parts to the tolerance necessary to preclude the use of compound would be VERY high.

What I do on a new system OR one that has just had new compound applied is to pw ON for a few min then shutdown for a while to let the system cool. The compound has now made it's way into whatever manufacturing imperfections that exist between the heatskink fan and the processor. Then just use the system normally.
Good to go.


Trusted Advisor
May 12, 2002
I've never owned a desktop/tower (4th generation and older) where the heat sink unit needed to be removed from the CPU in order to replace its cooling fan unit.
All the ones I've owned allow the cooling fan unit to be unclipped or unscrewed from the heat sink unit.
I've done this a few times to remove the dust from the cooling fan unit and the heat sink unit.
I've never had to remove the heat sink unit from the CPU.
I've never had to remove old thermal paste and apply new thermal paste.

You weren't clear in post #1 why you did what you did, so I'm curious.



Users Who Are Viewing This Thread (Users: 0, Guests: 1)

As Seen On
As Seen On...

Welcome to Tech Support Guy!

Are you looking for the solution to your computer problem? Join our site today to ask your question. This site is completely free -- paid for by advertisers and donations.

If you're not already familiar with forums, watch our Welcome Guide to get started.

Join over 807,865 other people just like you!

Latest posts

Members online