lapping a heatsink

[jordan]

what exactly is "lapping" a heatsink?
also- I have a global winfop 38, what would be a good peltier wattage to match to this heatsink, or do I have to go with watercooling? I have a 1G thunderbird currently overclocked to 1.21, it is getting hot though, just around 50 for full load- I used the thermal pad it came with, arctic silver 2 compound is on the way! I was told I might need to ???lap???my heat sink. Hopefully the Arctic silver will bring me down a C or two, if not, please feel free to include some peltier kit info for me

thanks!

 

[biztyke]

lapping basically means sanding your heatsink bottom flat. this should be done with wet/dry sand paper starting with 200 grit and gradually going up to 1500 grit. also, when doing this you should do it on a flat surface, like a piece of glass.

 

[dimmreaper]

Those "thermal pads" are just crazy stupid. I don't even recomend using them for non-overclocked CPUs. I bet the ArcticSilver brings you CPU temps down 10C. Just be sure to remove the themal pad. I bet lapping will bring your CPU temp down another 3-5C on top of the 10C you will lose with the ArcticSilver.

Let us know how it goes.

 

[LimeyGreg]

No one answered all of his questions.

I'm no expert with your CPU and HSF but I would say that if it is at 50c then your HSF is not going to be able to deal with the combined heat of your CPU plus the TEC. Of course, your present temps may be due to the thermal pad.

I believe Arctic Silver really only shines when the CPU surface and HSF surface are not flat - it performs well in large gap situations (relatively speaking, a large gap here is only a few thousands of an inch). If the CPU and HSF (lapped) are flat, then regular good quality thermal compound is adequate.

If your temps are still high after lapping etc I think you'll either have to go for a more powerful HSF combo or switch to water - my intuition is that water is probably the best bet. I may be putting my foot in my mouth here, but I believe water without the TEC would be best as I believe I've read that adding a TEC is far more trouble than it is worth when used on a Thunderbird, or any AMD for that matter.