Why my CPU fans got loud noise like spin very fast?

Loud fans are usually caused by dust if there is dust built up on the fan it can throw it out of balance and make it rattle. Just because you fan got loud doesn't mean you machine has any other problems than the fan.I would start by cleaning out the computer with compressed air. Clean off the fan blades and blow out the power supply and the heat sink for the cpu. Once this is done check your temps in the bios to see if your cooling good enough. then decide if you have other problem . A good cleaning often solves a lot of problems. Hope this helps

"I've had the same issue with a computer that is super clean, dust free. It was a bad video card that caused the fans to run high. I would swap out the ram stick to see if that could be the problem also.

Jim"

Hello! I have had this type of Dell power supply http://hardware.nl/power-supply/dell/gr3... and it started to make loud noise. I thought that it is brolen but tried to fix it. I remove the connectors and put it bach again. It helped, so you can try it too.

"[ *IMPORTANT*---> ALWAYS press the computer's main power button AFTER UNPLUGGING but BEFORE OPENING the case, this will release the ""left over"" charge. Also use an anti-static wrist strap when operating inside the case, these will help prevent electric discharge that can fry circuits. <---*IMPORTANT*]

First check for defects and obstructions by opening the case and inspecting the fan and it's blades for things like chipping, cracks, loose mounting brackets, missing or broken fan blades. Also check for anything that could be on or around the fan blades, either blocking the air flow or hitting the fan while it's spinning. Then while you still have it open, clean out ALL of the dust. Dust can insulate the heat, trapping it in the computer and causing it to overheat.

If it's clean from dust, the fan is in good shape and you're still having this problem then unplug the fan from the motherboard, close the panel and start the computer up. After it finishes loading completely, shut it down and go back in and plug the fan back into the motherboard. Close it up and start it back up, this resets the automation that turns the fan on/off and hi/low. Let me know if either of these work and if not I will be glad to provide further suggestions."

"I actually found a solution that involves checking whether your PC's processing power management option is set to ""active"" or ""passive"". I was able to change those settings to passive, and that stopped the fans from running at a high rate. This solution became evident after I made sure the dirt and dust build within the tower was not an issue.

Control Panel -> Power Options -> Edit Plan Settings ->Change advanced power settings ->>Processor power management -> select passive."

i have a problem in my PC ,any suggestion or help everytime i plug In the power cable in power supply socket automatically FANS spinning too high , no display no power on, just only fan working too high spinning. i checked the RAM but working in other PC also power supply ..