I have an Asus P4T motherboard and would like to upgrade from a P4 1.5GHz 400MHz FSB to a P4 2.53GHz 533MHz FSB. I can get an adpater to go from socket 423 to 478, but I'm curious if I could run the system at 533MHz FSB. The motherboard was built for 400MHz, not for 533MHz.
No you can't, at least for what you're doing. Those adapters only work for the Socket 478 Williamette core processors, which were made to ease the transition to Socket 478 for the big OEM's when production of Northwood core processors was still fairly low. Since you cannot get a Williamette core CPU at at that speed, and since since all the Williamettes sucked badly, you have no better option than to upgrade your board.
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