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My PC won't start after an abrupt power shutdown. The hard drive has not crashed or anything. The PC itself keeps coming on and going off without starting the OS. I have even switched drives but I'm still getting the same issue.

  • The computer tries to start, the motherboard/fan makes a lot of noisy revolutions, then computer shuts itself down. Then tries to start again ... (same cycle again)
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At what point did your PC lose power? Do you get ANY display on the screen? Can you see if there are any lights on your motherboard such as boot status LED's (see motherboard manual)? Was the computer fully booted at the desktop with applications running? This sort of thing is quite hard to diagnose without physical access to the machine. Could be a memory problem, try with one stick instead of two (if you have two). – Jay_Booney Feb 14 '11 at 22:45

Try a hard reset, unplug the AC and main battery if it is a notebook, remove the cmos battery for 15 minutes, reinsert the cmos battery with the same polarity as you removed it, plug in AC, start up, if you get a bios splash screen immediately enter the bios before Windows loads and set the date and time save changes on exit, see if it will boot into windows.

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An abrupt power shut down can cause an induced current and it might have damaged the IDE channels or maybe the BIOS. Can you try the drive in another pc? If it boots I'd guess you're looking at either a new BIOS chip or a new motherboard. Can you even replace the BIOS on MB's these days? I haven't done it in a long time, but a MB would probably be the way to go.

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There are some motherboards, usually fairly expensive ones, with removable BIOS chips, but they won't do you a lot of good without an identical board. I don't know of any that do have this where you can just buy the chip off the shelf. :) – Shinrai Feb 14 '11 at 23:08

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