Hello, I am trying to upgrade from a intel celeron d to core 2 duo E8400 and the system does nothing.
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What motherboard do you have? Celeron D to C2D 8400 is a pretty large change, i find it highly unlikely that your board supports the 8400, if you want to use the 8400 you will probably need a new board.
Your mobo will not support the FSB requirements if you're using the same board. Also good luck using the same ram.