motherboard, windows or other?

imported_SuperSkier

Junior Member
Aug 15, 2009
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This problem has really driven me up the wall. Can't seem to find where the problem originates or how to solve.

Phase I (current problem)

Several months ago, my system began restarting on power down from Windows (Vista Ultimate 32 bit). Power goes off, but after 3-5 seconds, the computer powers up and reboots. My workaround was to turn off main switch by power cord. Turning this back on later did not result in reboot - had to push normal power on button.

Phase II (similar, but worse)

About a month ago, after a power off, the computer began its new phase: It would power on briefly, then turn off (no POST, or more likely, POST failure). I continues to cycle like this until main switch is turned off. Starting up after turning on man switch resulted in same cycling and failure to complete boot up.

Deciding that it had to be my motherboard, I changed that from Gigabyte EP35C-DS3R to Gigabyte GA-EP35-DS3L. Eureka, all was well and it booted up. Until I shut down again, then it went into the Phase II recycling. Reasoning that it must be the processor, I changed that from E4500 to E8200. No luck. Pulled each memory bank and went with one at at time in different sockets. Memory is Corsair DDRII-800 (2x2Gb). Then I noticed that when the 12V supply for the processor was connected, the problem occurred, but not when it was removed - of course, no full boot either. Naturally, I switched the power supply - nothing - still recycles. Never liked my case anyway, so I changed that. Oh, BTW video is GeForce 8600GT.

Oh, having spent all this, I suddenly reasoned that maybe I should have tried resetting CMOS. Guess what? It worked. Now it booted. Short lived - on shut down, it restarted and cycled as before. Reset again, works fine again, recycles if shut down from Windows.

Reset CMOS again and tried hard shut down - holding button in for ten seconds. Works! Works repeatedly. Something must be changing BIOS on a Windows shut down. Same if I turn power off at the main switch. Lived with that a while.

Okay, I now have almost all parts for a second computer, so I bought memory and video card and tried that with the hard drives. No problem.

Back to the first computer (but it now has the E8200 processor: Bought a new hard drive and installed Windows fresh on that. Back to Phase I condition.

Does anyone have a clue what is going on? Any other info needed? Thanks in advance.

I'm posting this in motherboard and in Windows forums.
 

imported_SuperSkier

Junior Member
Aug 15, 2009
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Temperature shows as fine when I go to BIOS. Plenty of fans. New case, new ps, new motherboard (on the Phase II problem), new processor, new video card - only new memory hasn't been tried on Phase I (haven't tried new mb with new processor either, but ...)
 

Gillbot

Lifer
Jan 11, 2001
28,830
17
81
fresh windows install?
check to be sure there in nothing trapped under the board?
unhook tho power/reset buttons and try a different set?
 

imported_SuperSkier

Junior Member
Aug 15, 2009
5
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Fresh install of Windows Vista on a brand new hard drive.
Changed board to another case, but didn't check to see if there might be something touching (see below).
New case, new power/reset buttons.

One thing that I haven't tried is going to nylon standoffs for the mb. That'll be the next thing I try when I have a chance to take the system down and work on it.
 

Gillbot

Lifer
Jan 11, 2001
28,830
17
81
you don't need nylon standoffs as the mounting posts are designed for grounding as long as they are properly installed. Strip the system to the bare essentials and test from there.
 

imported_SuperSkier

Junior Member
Aug 15, 2009
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Already did that as I switched components: mb, processor, memory and video (no onboard, so had to install card).

This is a really strange one.