4,250Ghz maximum for my P4 650?

[selder]

I've got a P4 650 under a Zalman 7700-Cu at full speed on an Asus P5WD2-E and it seems 4,250Ghz (250Mhz FSB) is the maximum I can pull out of it ...

When I go over the 250Mhz FSB, let's say 251Mhz, SuperPi generates errors and 3Dmark06 crashes on the first CPU test ...

http://gallery.damn.be/d/9565-1/table.jpg

Is there any way I can push it beyond the 4,25Ghz with this hardware (this motherboard and the zalman cooler)

[TaPaKaH]

1) did you try to raise Vcore
2) 4.25GHz is already very good for aircooled Prescott

[selder]

Not yet ... I understood that Prescotts didn't liked upping the vCore? But I don't have any other options no? :)

It's just that this Prescott is holding my 7900GTs in SLI wayyyy back ;) Maybe I should get a P4D 805 :p

[TaPaKaH]

If you`re about to get a DualCore Intel -> go for 9xx series ... and search for C1 stepping ...
P.S. Prescott - like upping the Vcore. If the 4.25GHz is @ stock 1.4V - then you got a very nice CPU there... my hand picked Prescott can`t reach more than 4100MHz @ 1.4V (but the cooling is BOXed)

[SMa]

my P4 640 goes on air to 4.2 GHz (FSB 262) with 1.45v
so 4.25GHz is a good result for an aircooled 650

get a better cooler and you'll prolly get another 500MHz higher