Noisy CPU Fan? Slow it down with Speedfan!

Anybody who still runs an Intel Pentium 4 Prescott CPU (like me!) will know how hot it can run, and how insanely loud the fan sometimes becomes.
At startup the CPU runs at around 35C, but it can get up to 70C+, which is cooking. That's when the fan RPM goes up to about 4500 and the PC begins to levitate thanks to the updraft created by the fan :)

So what's the answer?
Well for starters, if you are technically inclined you can give this a bash;

1. Pop off the CPU fan and heatsink;
2. Clean and lubricate the fan - that will help it to run quieter;
3. Clean the old thermal paste off the underside of the heatsink and CPU itself;
4. Apply a new layer of thermal paste to the CPU - doesn't have to be much as the pressure from the heatsink will spread it evenly. Too much thermal paste can actually have a negative effect on the cooling of the CPU;
5. Re-install the heatsink and fan - make sure the heatsink is properly seated on the CPU - all 4 clips must click into place and this can require a fair amount of pressure. Just don't snap your motherboard in two...!
6. In my case, I did not seat the heatsink properly first time round - the result was that my PC would boot up, run for about 10 seconds and then shut itself down. That shows just how quickly the Prescott CPU heats up without proper cooling installed - 10 seconds is all it took for the CPU temp to exceed the safety threshold and shut itself down!

So that's the technical route... what if you don't feel like opening up your PC and getting your hands dirty?
Well help is at hand - enter Speedfan.

Speedfan is awesome free software that allows you to monitor voltages, fan speeds and temperatures in computers with hardware monitor chips.

Unlike other temp and fan speed monitoring software, however, Speedfan is in its own league because it allows you to control fan speeds, thereby reducing noise and making your working environment that much more pleasant :) Download it here.

Configuring Speedfan is a bit of work - make sure you read the included "Help and How-to" document thoroughly before making any changes to your system settings. Thing is, you want to reach a good balance between CPU cooling, and how much noise you can tolerate.

I can say that it works amazingly well though. On my system I had to disable "Q-Fan Control" in the BIOS in order to allow Speedfan to work its magic. Once I did though, the results were amazing.

Normally, even though my CPU was running at a relatively cool 35C, the fan would gradually spin faster and faster, eventually reaching upwards of 4000RPM. That's a lot of noise right there.

After installing Speedfan though, I can now fine-tune my CPU Fan speed on-the-fly as I work, just by changing a single numerical value in the software.

Take note of the "Speed02" value below, and check out the associated "CPU0 Fan" speed above that:

Change "Speed02" to anything from 1-100%, and your CPU Fan responds immediately!

Again, very very important here is to keep your eye on the CPU temp - in my case 37C which is perfect. If this starts climbing then so should your "Speed02" value, in order to provide the necessary cooling.

Hopefully you can find a happy medium between noise and cooling - just don't go do something silly now and switch your CPU Fan to 0 or something... I won't take responsibility for fried CPU's and motherboards :)