If you tried everything and didn't solve it, it's unsolvable. Then it's time for a new motherboard (allthough maybe you tried that also, you forgot to tell).
http://forums.cnet.com/7723-6121_102-522736/boot-up-fail-with-checking-nvram/ is a prior discussion about resetting the BIOS to its default state. But since that's the first thing anybody would do it's certainly included in your "everything".
Kees
Computer hung up on checking nvram
tried everything, any ideas.
Colin

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