The two common areas are:
1. Motherboard capacitors.
Very easy to spot. Here's pictures -> http://www.pcstats.com/articleview.cfm?articleID=195
Fix? Replace the motherboard.
2. Power supply has degraded.
Along with the capacitor issue above, ELECTROLYTIC CAPACITORS age and lose capacity. A smaller power supply and heat accelerates the aging which is surprising to some that 1 year can be all that it takes to start seeing issues.
Since 450 Watt PSUs are in the 20 something range, there is no need to skimp here (a duron 800 won't need that size, but why skimp?) and is just a little cheaper than the motherboard.
It's likely to be one of these two items.
Less likely, but worth replacing is the CMOS BATTERY. It's a few dollars and if you want to make sure, just replace it.
Bob
I'm trying to troubleshoot a problem for a friend of mine, long distance. I built the system for him, but dont have it in front of me at this time. First, the system: Duron 850, on generic board with 40 gig HD, 512 memory, running WinXP home. The owner now tells me that when he turns the system on, the floppy drive grinds, and no boot. I'm still trying to get him to tell me what, if anything, the screen is saying, or if any fans or lights come on. He has replaced the floppy drive, and the grinding has stopped, but the computer still does not start. He states he must press the reset button several times to get it to boot. I'm thinking power supply is ok since he says once computer is up and running, all is well. I've heard of having to run "bootfix", but not too sure if that would help the situation here. Any suggestions would be greatly appreciated. Pat Hahl

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