New PC Build

CPU Cooling, Heatsinks, Lapping

Lapping basically involves sanding down the base of the heatsink with sandpaper to make sure it’s completely flat. Why do I need to do this? Well the heatsink gets attached to your CPU which generates heat. This heat then transfers into the heatsink, away from the CPU and cools it down. Then, an optimally placed fan will push the heat from the heatsink out of the case. So the flatter the base of the heatsink, the better contact it has with the CPU, enabling more efficient heat transfer.

Thermalright Ultra-120 Extreme

If you’re not going to overclock you probably do not need to lap the heatsink unless the base is in really bad shape (really convex, concave, or warped). But when you’re running a quad-core CPU like the Q6600, it will generate a lot of heat, so you’ll need to lap if you’re overclocking. This reduces core temperatures and will help prolong the life of the CPU. You’ll definitely need a good heatsink since the stock one just won’t cut it. The Thermalright Ultra-120 Extreme is pretty much the best there is when it comes to heatsinks. You’ll find dozens of reviews online that show the TU120-Extreme has the best cooling performance for quad-core chips like the Q6600. By the way, this heatsink is HUGE – I really couldn’t tell it was this big through pictures online.

Lapping the Heatsink

My heatsink had a pretty flat base already but I wanted to smooth it out. I did an okay lapping job (not all that great but good enough considering I’m a noobie). However the CPU still doesn’t sit flat against the heatsink. You can test this by placing your CPU on the heatsink base and then shining a flashlight on one side and see if light slips through between the heatsink and the CPU. There are gaps on the side but the area right above CPU cores sits flat against the heatsink so it should be okay. We shall see. But this means the CPU’s integrated heat spreader (IHS – a protective metal covering over the CPU cores) isn’t flat either and I could probably reduce the temps if I lap the CPU.

Proceeding With Caution

However, I REALLY don’t want to lap the CPU because it isn’t like the heatsink where it’s all metal and it doesn’t matter if it gets wet. The sandpaper needs water as lubricant and if I get even a tiny speck of water on the chip, it’s toast. Lapping the CPU will also void its warranty and although processors rarely fail, I’m still reluctant to risk it. So for now I’m just going to go ahead without lapping the CPU. But if the temperatures are too high when I overclock and stress test, I might take it out and lap it. I might have to relap the heatsink too, I’m not sure. I just know all this lapping is a huge pain in the ass and I really want to move on.

Thermal Compound (Artic Silver 5)

But then again I know that if I get it right early, I’ll be rewarded with a better overclock and lower temperatures. I was going to finish putting it together tonight but I didn’t want to have the Artic Silver 5 thermal compound set in overnight before I could really burn it in (heat it up with CPU stress tests). Thermal compound is what you apply between the CPU and heatsink. The compound will fill in the microscopic spaces and push out air pockets to ensure better heat transfer between the CPU and heatsink. Arctic Silver 5 is pretty much the best thermal compound available right now. You MUST apply thermal compound; if you don’t, heat transfer will be very poor and you’ll notice very high temperatures and risk burning out your processor. After I finished lapping, I cleaned off the heatsink and CPU with ArtiClean.

The saga continues tomorrow …

I re-lapped the heatsink. Still gaps on the side. CPU IHS surface is definitely convex. Going to go ahead with the build anyway.

To be continued …

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