What Happens When You Put Higher FSB CPU in a Lower FSB Mobo?

[trowand]

What happens when you put a higher FSB CPU in a lower FSB motherboard? (of the same socket, of course) For example, can you put a P4 800Mhz FSB CPU in a mobo with a 533Mhz FSB? My exact situation that I'm looking at is replacing an OLD Socket A AMD Duron 750Mhz (w/200Mhz FSB) with a Socket A AMD Duron 1.8Ghz (w/266Mhz FSB). How will it perform? If it defaults to the lower bus speed of the mobo won't I lose overall CPU speed?

[Cricket]

You need to check if the motherboard supports the new CPU vcore voltage or not. If not you could fry the CPU or damage the motherboard.

If the motherboard does support the vcore voltage setting then the 266MHz FSB CPU will just run slower when on the 200MHz FSB. In this case the 1.8GHz Duron will probably run at 1.3GHz.

Cricket

[glc]

Actually you must use the motherboard manufacturer's CPU compatibility chart. If it's not on the list, don't use it.