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pappaG

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Mar 9, 2007
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:oops:
I am new here but have built several systems in the past. This one being the most ambitious. Asus crosshair MB, SLI 2-asus8800GTX, 2gb kingston 800 (4-4-4-12) matched pair, AMD athlon 64fx 2.8ghz CPU ,thermaltake toughpower 850W PSU, ect.
The problem is that once everything was installed in the case nothing worked except the MB LED'S. Took the MB out of the case and just left the CPU, memory, 1 video card,keyboard / mouse/monitor connected. Still have LED no beep no display. The fan in the PSU did not come on and the CPU fan either. Have a PSU tester and the PSU checks out Ok and PSU fan starts up. Given the quality of the memory don't suspect the RAM. RAM in correct slots for matched pair. 24 pin and 8 pin PSU pluged in correctly on MB. Any thoughts before I RMA the MB or do I think I know more than I do.
pappaG
 

polarity

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Mar 9, 2003
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Used to have an XPC that'd go dead if the video card was taken out then put back in.

The trick was to put the card in, then disconnect the power, pull the CMOS battery and switch the CMOS jumper for 30s (not easy to get to the jumper or battery with the card in though ;)).

There are a lot of capacitors on modern graphics cards, and they hold enough charge to mess with the CMOS as the card is put in/out. When everything is assembled there are ground lines for everything, but sometimes when you unplug a card those lines are disconnected before others so electricity can end up going places it shouldn't. Doesn't damage anything as it's a tiny amount, but CMOS memory gets scrambled with only a little, as it needs to run on such a small amount.