Volts

[asmithz]

I think my computer is messed up or something, it keeps making noises, and reving. Fans speed up then slow down.. I think the volts are wrong. how do i check and fix it?

[Darth Sushi]

Many MBs will show actual voltage and fan speed in the BIOS.

[DrBeerMan]

try downloading cpuz http://www.cpuid.org/cpuz.php
and see what it says your voltages are..

[clocker]

Many MBs will show actual voltage and fan speed in the BIOS.

Many will show something in BIOS but whether it's accurate or not is debatable.
The only way to really know is to test with a multimeter.
My DFI has reported the +12v line as 11.71v with two separate PSUs (good ones too, not crap) when the multimeter shows 12.1v or so consistently.

The phenomonon you describe does not sound like a PSU issue...more like thermal throttling of the processor.

[Appzalien]

What kind of PC is it? Did you build it yourself or is it a store bought PC. Most store bought PC's have a short life because they use inferior Power supplies to keep costs down and can cause damage to the motherboard over time. Unfortunately they are also often proprietary power supplies made for that specific machine so can't be replaced with just any supply. And if you try to buy one from the PC manufacturer they sell you another inferior supply at some ridiculously high price.

[asmithz]

What kind of PC is it? Did you build it yourself or is it a store bought PC. Most store bought PC's have a short life because they use inferior Power supplies to keep costs down and can cause damage to the motherboard over time. Unfortunately they are also often proprietary power supplies made for that specific machine so can't be replaced with just any supply. And if you try to buy one from the PC manufacturer they sell you another inferior supply at some ridiculously high price.

Built it all myself

[Snee]

If you've got an entry in your bios called pc-health, take a look at what options you have, see if it has some sort of fan-speed regulation/smartfan option.

My nforce2 board lets me set a temp I want my fans to rev up on, if I want that. I can also choose to let it keep them at full speed all the time, or keep the speeds at a constant low.

I found the the fan on the gfx card was much louder than the rest of them, so I've got them running on full, pretty much without any added noise.

There's also a program called speedfan which lets you control these things through windows, with the right mobo.