Heatsink mounted then re-mounted: would you re-apply thermal paste?

Superlevure · 3 Apr 2022 at 05:55

I mounted a brand new Noctua nh-u12a (which arrived with some bent blades :rolleyes:

) then realised I had put it the wrong way (it wasn't leaving much clearance for the ram) so I removed it, checked the thermal paste (no spill, spread evenly) and re-mounted it the right way.

It didn't feel wrong to re-mount it but I thought I'd get some advice before I proceed.

heatonpkmassive · 3 Apr 2022 at 10:39

Just my opinion but yes I would.

Quartz · 3 Apr 2022 at 11:00

There's no need to reapply thermal paste in such a situation. It's fresh, not cured - let alone dry - so there's really no problem.

Dg834man · 3 Apr 2022 at 12:31

Agree with Quartz it will be fine

Glanza · 3 Apr 2022 at 14:48

You'll be fine, no need to reapply if it's that fresh, only time I'd do it is months down line if you have to take cooler off.

heatonpkmassive · 3 Apr 2022 at 19:29

Even if it was mounted the wrong way and you'd refitted it the right way?

You're probably all correct, but I'd only do that if it was going on the same way it came off.

heatonpkmassive · 3 Apr 2022 at 19:30

I'm thinking pre applied paste here, just normal paste I wouldn't bother.

Skilid · 5 Apr 2022 at 15:22

Re-using paste is perfectly fine so long as it's in good condition and still malleable.

ChocAndGray · 5 Apr 2022 at 15:38

Yeah in those circumstances it would be absolutely fine.

Trying to mount a D15 and I hadn't aligned the cooler properly with the screws to tighten and ended up lifting the cooler up and then down to re-align and I had no issues.

As has been said already because it was that fresh there'd be no ill effects.

Gavin D Staveley · 25 Apr 2022 at 14:37

If it was me, the amount of thermal paste and time involved to reapply would be negligible so I would just redo the paste.

The purpose is to ensure full contact between the heatsink and the processor surface area for maximum thermal transfer.

There cannot be any air-gaps within the surface area otherwise thermal transfer for dissipation will be hindered which may cause your processor to overheat.

Without thoroughly cleaning both surfaces and reapplying fresh thermal paste properly risks introducing airgaps due to the paste already being thinned-out and thus cannot spread to fill in the gaps when it is compressed.

The major manufacturers expect fresh thermal paste to be applied every time their service-maintence-agreement/warranty-repair technicians reseat the heatsink/fan on a processor.

Of course this is a textbook answer and there is the possibility of getting away with cutting the corner however for me it is not worth taking the risk to save a few minutes work.