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how do you oc 2 Xeon 666Mhz?

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Oct 15, 2002
Board: IWill DCA200.
2 PIII Xeon 666Mhz

I tried to change the "CPU Clock" from 666Hmz to 800, 933, 1Ghz.. but when reboot the CPU clock remains at 667Mhz or even drops down to 533Mhz.

I got this for free.. So, any idea how to overclock it? I was running an TBird Athlon 900Mhz and now this seems a little bit slow. I guess so, but it "feel" fine with my SCSI drive.

these 2 CPUs are using slot 1, and they are huge!
They are always cool with all my cooling anyway. So now, it's all for overclock!! please advise.

They are running on IWill DCA-200 mobo with 256Mb Rambus. and I have a Radeon 7200, and an Adaptec 29160 ...

Well, my guess is that you're selecting those speeds from a menu and the BIOS is trying to change the multiplier of the chip so it'll run at that speed. Not the way it works, unfortunately. You need to find FSB options (if the board has any, many Xeon boards don't), and raise that progressively to OC.

Past that, I can also tell you those are not slot 1's but slot 2's. Slot 2 was Intel's Xeon format, and yes they are huge. Do you know how much cache those things have?
32K L1 and 384K L2 for each of them... it's a little bit little i guess :(

the board will run at 100Mhz or 133Mhz FSB, but it's already running at 133Mhz. Is there a way we can change the multiplier (currently 5)? I looked on the boardbut found no jumpers or the like.

No way to change multipliers on Intel CPU's nowadays. If there are no other FSB selections then you're out of luck. :(
jedivn said:
32K L1 and 384K L2 for each of them... it's a little bit little i guess :(

No, that is your Athlon cpu. The Xeon 133Mhz fsb cpu´s has 256kbyte L2. Apart from a few minor monitoring capabilities it is the exact same thing as the Pentium 3 Coppermine.
I just sold a pair of P3-800 Xeon Engineering Samples. They have unlocked multipliers. Other than ES chips, your only option is FSB. My Supermicro GX board has 100, 103 and 112 for FSB options, but my 450 Xeons won't do the 112. I've heard that some Xeons have speed regulation circuitry so they can only run at their default speed.