Reapplying heatsink

[htid]

I was transporting my comp and my Arctic Freezer Pro 7 kinda came loose, so I had to take it off. Both the cpu and the heatsink still have the rest of the thermal paste on, so am I supposed to wipe it off and apply new paste, or can I just reattach the heatsink now?

If I have to buy some more, I'll need to do it tomorrow so I'll go to Maplins, but not sure what kinda stuff they will have. Will any do (with the more expensive ones just working a bit better) or will cheaper ones from Maplins be no good?

Also when it's applied, how tightly should the fit be? I always remember when I built my PC, fitting the heatsink was the hardest thing, it seems to always wobble a bit because the actual heatsink isn't fixed to the metal piece that is touching the CPU, it kinda pivots.

Anyway cheers for any help,
Chris.

[Mithrandir]

If I were you I wouldn't reuse the thermal paste. I'd apply a fresh lot.
Maplins seem to have Antec and Akasa ones which I'm not sure about.

[Golden Dragoon]

Don't reuse what is there again, you will never line it up properly and end up with air pockets in between your cpu and heatsink.

As for what brand to buy for the best thermal performance, it really makes no difference at all, Dan at Dans data tried loads of them and found no difference, and infact found that tooth paste, vegimite (marmite?) and water all perform just as well if not better than thermal pastes

[htid]

Thanks both of you But anyone have any ideas about how tight the heatsink should be?

[htid]

Also, there's still some trace of thermal paste on the heatsink, can I use some wetdry sandpaper to lap the bottom of the heatsink (NOT the cpu) and get rid of the residue, or doesn't it matter?

[peterb]

Get some Akasa TIM cleaner from Maplins and a can of Isopropyl alcohol (about 4 and 6 punds respectively)

Scrape off as much of the thermal opaste as you can with a non metallic scraper and then clean off the residue with the TIM cleaner. Finally wash it with the IPA and allow to dry. Use a lint free cloth and don't touch the surfaces after they have dried. Then apply a small amount of the thermal paste of your choice (about the size of a match head) to the centre of the CPU die and replace the heatsink. Once the heatsink is in place, give it a slight twisting mothion a coupole of times to help distribute the paste.

When you switch on, the temperature will climb rapidly until the paste flows, when the temperature will drop. Depending on the type of paste, the thermal performance will improve over the next few hours.

Both the Akasa and Actic web sites have detailed instructions.

Some people advocate using vinegar - not tried it myself and as it is an acid, I wouldn't recommend it! (Do you want to run the risk of getting an acid over your mobo?)

It sounds as if the heatsink wasn't clipped on properly if it fell off. The clips provide sufficient contact pressure for ciorrect operation.

I would NOT use wet and dry to try lapping the surface. The important bit is a flat surface and unless you have access to a workshop, you run the risk of getting a convex or concave surface. Absolute smoothness isn't necessary, the thermal paste fills in any minute surface imperfections, but as its thermal conductivity is poorer than direct metal to metal contact, you need to use the minimum amount so that it doesn't form a barrier.

Silver loaded compounds are reputed to be more efficient thermal conductors, however as they are electically conductive, there is a small risk of short circuits if it is squashed out over the CPU connections (ie, you use too much) so I prefer a non-conductive compound. (I used Arctic's MX1 last time I changed a heat sink)

[KowShak]

Silver loaded compounds are reputed to be more efficient thermal conductors, however as they are electically conductive, there is a small risk of short circuits if it is squashed out over the CPU connections (ie, you use too much) so I prefer a non-conductive compound. (I used Arctic's MX1 last time I changed a heat sink)

I agree that silver based compounds tend to outperform most bog standard greases and thermal pads but ceramique out performs silver based compounds in the reviews I've seen.... there are other non-silver compounds that do too.

[htid]

So still, nobody has answered whether or not the heatsink should be slightly wobbly from side to side (or up and down if you're looking at it face on).

Here's a quick video, didn't have anywhere to upload so hope my sisters youtube account is ok Does that look ok?

...oh well seems youtube takes ages to upload or whatever, i'll update later but it definitely doesn't seem right, as the heatsink isn't contacting with the cpu, it's pivoting.

Anyway have to wait till the video is uploaded.

[acrobat]

Get some Akasa TIM cleaner from Maplins and a can of Isopropyl alcohol (about 4 and 6 punds respectively)

is the TIM cleaner by itself not good enough? Do you need the alcohol too?

[htid]

Seems fixed now I used just the TIM cleaner acrobat, cos the back of the thermal paste says

"clean off with isopropoyl OR Akasa TIMclean"

[acrobat]

Ahh cool thank you. I was wondering for a bit, cause I just use the TIM cleaner and my temps are bad, so I wondered if the TIM Cleaner needed cleaning off too