Fans

The noisiest part is usually the CPU fan: the Intel-supplied fan-heatsinks are particuarly loud,although they do provide good cooling. Some BIOSs allow you to slow the CPU fan downautomatically when it is not too hot - if this option is available, turn it on. Also, you can get 3rdparty coolers, which are designed to be less noisy: for example, those made by Zalman. Noisypower-supplies simply have to be replaced with quieter ones. The case fans can be sloweddown by using fan-speed controllers, or resistors (but beware of ensuring sufficient cooling).Motherboard and lower-end graphics-card fans can usually be replaced with a small passiveheatsink. Large diameter (120 mm), high quality fans are much quieter than small diameterones. After a few weeks, dust and debris can accumulate on fan blades. Keep them clean toreduce noise and increase efficiency.