Lately my computer has been making a lot of noise. My computer case is pretty large, it's a full-ATX sized desktop case and has lots of fans. So I'm generally used to quite a bit of fan noise, but it has been peculiarly loud of late. I had some friends over the other night to play some board games and they mentioned that it was really loud. Actually to quote they said, "It sounds like it's going to explode!" That was the last straw. No longer was I going to let my computer ruin my social gatherings.

After observing the computer while it was running I was able to determine that the sound was coming from the fan on my processor's heatsink. I tried to think of why it would be running so loudly and and came to form a speculation.

I unplugged my box of all cables and peripherals and took it to the kitchen table where I could get some light on it. It turned out that my theory was correct. The culprit was, in fact, dust.

You can't really tell from the picture, but there is dust lining the entire top part of the heatsink on my processor, directly beneath the fan. This presents a problem because the purpose of a heatsink is to absorb and dissipate heat. The heatsink fan's job is to help in the act of dissipation by pushing air across the surface of the heatsink to cool it down. The problem with dust is this: if it acts to obstruct the air from getting to the heatsink then the heatsink never cools off and remains hot.

The reason my fan was so loud was because it was running really fast! You see, when the processor gets hot there are sensors that alert the fans and the fans will start to run at a faster speed to instigate the cooling process. Because the processor wasn't getting any cooler, the fan was always running at it's fastest speed and made a lot of noise.

I used some q-tips and tweezers to remove the majority of the dust. I could have taken the heatsink off of my motherboard and removed the fan assembly, but I was concerned that I'd need to reapply thermal paste to my heatsink after taking it off of the processor, and I didn't have any handy. After removing the dust, I reconnected my PC and it has been very quiet. If you're computer is making a lot of noise, I'd definitely recommend checking for and cleaning dust off of all cooling parts.