Scratched Surface

[idno3]

I recently went about installing an NF-U12P on my new 920, and I kind of screwed up.
When I was trying to screw in the mounting brackets to the heatsink, my screwdriver slipped, causing a moderately deep scratch across the right side of the heatsink.

Would this majorly effect the performance? It's no where near the middle of the heatsink, which as far as I know, is where most of the heat transferring takes place.

I was planning to set it all up, then check the temps. If the temps were too high on stock speeds, I would probably consider lapping it. As of now, I'm highly inexperienced at lapping, so I'd rather use it as a last resort.

Any feedback would be appreciated.

[bojangles]

Where on the heatsink? The fins or the contact plate? In either case you should be fine. The thermal compound should mold into the scratch and keep contact between the heatsink and CPU.

[idno3]

It was the contact plate.
Good to hear I'll be okay.

Also, is it necessary to spread thermal compound? In my manual, it said to put a small drop in the middle of the CPU, and then just put the heatsink on.
Didn't say anything about spreading.

[JD]

If it's a deep scratch then lapping would be a bad idea. You'd have to take off way too much so then the heatsink wouldn't have good contact pressure on the CPU (unless you modify the mounting stuff).

And yeah, pea-sized dab of thermal paste in the center of the CPU should do fine. The pressure from the heatsink will spread it out for you.

[idno3]

Alright, thanks guys. :D

[bissa]

is there anything wrong with pre spreading the paste to make sure it hits the edges? because the pressure would still even out the amount there.

[JD]

Originally Posted by bissa

is there anything wrong with pre spreading the paste to make sure it hits the edges? because the pressure would still even out the amount there.

Well everyone has their own opinions.

For me, a blob in the center is just easier and cleaner. If you like spreading it then fine, but make sure its a decent amount so when you stick the heatsink down, the air bubbles can get pushed out to the edges. If it's too thin, I'd imagine you'd get little air pockets stuck in.

[bojangles]

Plus it's not like the CPU is actually under the entire IHS. It's only located in the centre of it.

[MpG]

I've always felt that if you've got enough thermal paste on that you can spread it out to cover the entire processor, you probably have too much paste on.

[silent1mezzo]

I've used a moderately deep scratched HS and it did increase the temps (7-10 degrees). Try it out on yours, you may not notice any temperature differences. If the temps are too high though you may need to go with a new one (or lap the current HS).