Check the sticky at top of page.
Are you sure you've tested it 'barebones'? No USB headers etc etc attached? Checked front panel leads for reversed position? No internal cards or drives attached? (Even the power lead connected to a drive can cause a problem - disconnecting the data cable isn't enough. Reset CMOS?
The 7800GTX is a very recently released card. Perhaps the motherboard has 'issues' with it and might need a BIOS update before it will work with that card?
Catweazle
Grandad
4,335 posts since Mar 2004
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If you have both worked through the step by step instructions in this pinned topic:
http://www.daniweb.com/techtalkforums/thread27079.html
and still cannot get a 'bare bones' configutation to POST then yes, perhaps it is time to get a technically qualified person to look at it for you.
Catweazle
Grandad
4,335 posts since Mar 2004
Reputation Points: 229
Solved Threads: 149