Multipler is there for intel to set to mark on their processor speed for the market according to the grade of the processors based on stable default speed at a certain voltage.

QX6700 and all the extreme processors are unique in that you are free to set the multiplier to that u desire.

Your problem is most likely that you are pushing your RAMs too hard, When you get a stable cpu speed at 1:1 you can adjust the ratio to 2:3 or 4:5 so that your RAMs would be at 1000MHz or so.. adjust the RAM timings (5/5/5/18..6/6/6/24.. 4/5/5/18 etc..5/6/6/20) and voltage accordingly(up to 2.2 would be ok)

If 280 fsb is all you can do the by all means increase the multiple to 11.. that would bring the cpu to 3.08GHz. I reach 370 by dropping my multipler to 9.. to get to 400 and beyond I may have to drop to 8 or 7, all the while keeping the cpu vcore within 10% the default voltage. There is also chipset/FSB/bus voltages to consider. Increase FSB speed would be better than multipler increase is because it increases bandwithwidth for more data feeding the 4 cores.

haha since thread closed ill tumpang here:
so basically i should be maximizing FSB more by lowering the multipliers? can provide more specific details on doing so? like the vcore/vfsb voltage settings etc etc

Trial and error(and a lot of time/testing).. no short cut .. could also be a limitation of the chipset.. (generally I dont increase voltage of any part more than 10%) ... that is why if you are impeded by fsb.. increase the multiplier. 3.0GHz at default voltage is no problem for My 2 quad cores.

and may i know the default vcore again?

1.35volts ..... most likely

So this thread has evolved to a quad core thread again... I started one 7 mnths ago... but was combined with the dual core conroes..

Quazacolt... try backing the fsb a little.. say 345MHz... to make sure it is not Ram speed issue try running one instance of orthos stressing the RAM... My cpu core 3(4th) is also a culprit that prevents me from going beyond 370.... Primming only the 1st 3 cores (1 hour or so).. i was able to go to 3.7/3.8GHz and ran some Pi test

Why is that happen? So when u disable core 2 and 4, is that mean ur system is not rock stable right?

Does anyone here know if the Kentsfield QX6700 ES has any problems with the Asus P5W DH Deluxe mobo ?

hmmm... i always wondered how come dual core has lower clock...

anyways, managed to clock my cpu to 3.1 ghz with 310 fsb and 10 multiplier. everything is stable cept my core 4 is always throwing a fit on me on orthos :/

my 4th core is stable at 3.4Ghz at 1.4/1.425v cpu voltage. beyond that will error no matter voltage applied. The other 3 can go to 3.7/3.8 or so. at 1.55v or so

hmmm... i always wondered how come dual core has lower clock...