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I have a problem with my PC. These are the symptoms:

  • CPU cooler makes 2x louder sounds
  • Green light indicating whether the PC is on doesn't show anything. The PC is on.
  • Red light (besides green one) is always on.
  • Green light on monitor is blinking.
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have you try power cycle? same symptom? can you go in to the BIOS? – chmod May 8 '12 at 12:16
Check if you have a internal system speaker. Read your motherboard manual and look for the part about error beeps. – Pieter May 8 '12 at 12:16
Seriously? edit this and describe the problem properly. – Paul May 8 '12 at 12:16
Yes, I tried power cycling, i can't go anywhere screen is all black. Mouse led is off too. – user1019892 May 8 '12 at 12:25
Is this PC connected to a surge protector? – CharlieRB May 8 '12 at 12:57

This question is very vague and hard to answer considering the lights you have mentioned are different for every case or motherboard ( what is red light? hdd activity? ), but by the sounds off things, if the cooler is running then its getting power, so i doubt its the power supply. I would nail it down to motherboard, just because you mention the "green light" isnt showing which should still show even if ram or cpu wasnt working.

EDIT: also leave the computer off for a while and see if the cooler still spins fast. if soo then its probably a corrupt bios.

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Red light shows cpu activity, because when i plug off both hdd, it still on. – user1019892 May 8 '12 at 12:34
I never actually heard of cpu activity from led, i could be wrong but the 3 computers I have all indicate hdd activity via red lights. whether its relevant or not it still seems to be a motherboard issue. Just for the fact that you say the power led isn't showing anymore, and I recall a bad bios flash i did once which resulted in not monitor display. – Edhen May 8 '12 at 12:39
I didn't flash my bios, should i try to remove cmos battery for a while? – user1019892 May 8 '12 at 12:42
from what i recall, the cmos battery wont actually reinstate the bios, it will only reset the settings. depending on your motherboard, they may have a rescue method (check your manual, or look it up online). sometimes its just a matter of a usb stick but you may need access too another computer to get the files needed. But do not rule out anything else, there is still possibilities that it may be ram or cpu. try popping out a ram stick then switch them arround, leave one out etc. just too rule it out before other more hands on attempts. if you have spare parts they would be helpful too. – Edhen May 8 '12 at 12:49
Also if check the manual and see how it generates code errors, eg. it may be beeps and if your motherboard has a connection to a small speaker then it should be beeping at you unlike a mother board I had which displayed led codes. If its suppose to generate beeps or some way off alerting what the problem is then its not doing its job and most likely means its bugggered (motherboard). – Edhen May 8 '12 at 12:54

To start, unplug the computer completely, press the power button while it is unplugged. The fans and such may lurch a little at this due to residual power in the capacitors on the mother board and in the power supply, that is what we are eliminating. Restore power and attempt again to start the computer.

If that does not work, repeat this time removing the cmos battery or setting the clear cmos jumper prior to pressing the power button while unplugged.

If you are still having issues, disconnect everything from the motherboard except, video, ram and CPU. Attempt again to start the computer.

If your issues continue try using a different power supply. Cheap power supplies have a life expectancy of about 6 months in a busy system.

If your issues continue remove and reinsert your RAM. Try again.

If your issues continue remove and reinsert your CPU. Try again.

If your issues continue remove and reinsert your Video.

If your issues continue locate a replacement video card. If you have onboard video this is also applicable, get or borrow a card that can be placed in a socket and attempt to boot with it.

If your issues continue replace your RAM, or try only using one half of it and in different sockets.

If your issues continue replace your CPU.

If none of this has worked to restore your system your mother board is likely dirt and you will need to replace it.

If one of the above steps worked you have likely found your problem. If you removed everything to get to this point add one component at a time back to the system until you are fully functional, doing a boot between each addition.

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Might as well add take the motherboard out and put it back in before you start buying new parts... I have seen small pieces of metal get caught behind the MOBO and ground it... – Not Kyle stop stalking me May 8 '12 at 15:22
Often it is easier to come by a spare video card or other components than it is a mobo. Especially with todays games requiring a new card for each new game. I wasn't suggesting he buy parts, as I agree it sounds likely it is either the mobo or video, video is probably on the mobo. – AaronM May 9 '12 at 0:34
I took replace to mean buy since the user never indicated having spare parts... – Not Kyle stop stalking me May 9 '12 at 12:36

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