pentium 4 fsb 400mhz

[idata]

can processor 800 mhz fsb worked at mainboard 400 mhz fsb?

if worked, any effect to computer performance?

[idata]

Hi!

800mhz fsb cpu not same as 400mhz mainboard socket

(most likely LGA775 CPU vs Socket478 MB)

Socket 478 will suppoprt up to P4 CPU's with 400mhz FSB.

CPU's with 533+ MHZ will not fit Socket 478 (this covers all dual-core CPU's)

However, if, when using a CPU with a higher FSB value (IE, e8xxx-series CPU w/1333 FSB on a 1066 MHZ FSB mainboard), the system should work without damage to the CPU, though at reduced performance (therefor is not recommended.)

[idata]

to hythos : so,if i put pentium 4 socket 478 with 800mhz fsb to mb socket 478 max support 400mhz fsb,it cannot be worked??

or it still worked,but in reduced performance?

[idata]

Hmm sort of. Knowing the MB spec would help most, though CPU voltage is different from 1.5 (800mhz) to ~1.7v(400mhz) ; Verify per CPU, then adjust on the MB. MB may have auto-sense with soft-set through CMOS, or jumper.

** Note - CPU will run at 1/2 speed rating - IE, P4@ 2.8ghz/800 = 1.4ghz/400