Can I used a 400fsb cpu on a motherbiard that support only 533/800?

hi! I just got that question I have a emachine and mb die it is a microatx but I can’t find a mb microatx that can support my cpu and it is a celeron 478 2.6 400 fsb and all mb that I find they only support 533/800 so I was wondering if i can put my cpu and just make change on the bios manually down to 400 fsb?

thanks again for the help!!

Unfortunately it’s not possible


it MIGHT be possible, but what sux is it might not boot. I’ve popped a northwood core celery in a gigabyte 865 MATX mobo, and it worked. It said something about not recognising the CPU though. It ran it at 533 fsb anyways, instead of 400, so it was running @ 3.3ghz!!! It was a newer D1 stepping northwood celery out of a POS dell that had it’s MATX mobo die. Out of curiosity, I popped that CPU in a mobo I ordered as a replacement for a friend’s machine. I was gonna order the same mobo for that dell, but I haven’t heard from him since I told him about it, so it sits here dead. Now I won’t guarantee you’ll get the same results, or if your CPU will work @ 3458 MHZ, but it might! I would try it in another mobo first to make sure it can OC that far, and unless it’s a newer D1 stepping celery chip, it probably won’t. C1 chips puke @ 3-3.2ghz tops usually, without a ton of core voltage, and better cooling. Even if it’s D1 stepping, my 2.8 ghz chip BARELY will run @ that speed, and it’s a D1 stepping P4. Allthough a celery has a better chance, because it’s got less cache, they didn’t put the good cores on them, and for some reason, the higher the multiplier, the harder it is to OC :doh: . So, I would advise against taking that chance. Allthough some boards will run @ 400 fsb even though they aren’t labeled to do so, but the only way to know that is to try it. I know certain intel 845 chipset based mobos can do it. Speaking of which, MCM electronics has an 845 based chipset Intel brand mobo that does 400 fsb for $60. It has onboard video and gigabit lan! I built a system for a friend out of one, with a 2.53 P4, runs great! I dunno if they have any in stock right now though, I was thinking that might be a good replacement for this dell though. :iagree: