core i7 950 OC problem

[kayawish24]

hello....

(my system specs are below in my signature)

 

Now i dont know that is my i7 950 D0 is bad batch or i am doing something wrong in overclocking.my Overclock is 10 hours prime95 stable @ 3.7GHz and the settings i used in bios are.

 

23x multiplier

BCLK 161

DRAMFrequency 1614 MHz

UCLK 3227 MHz

 

8-8-8-21

 

CPU VTT 1.22

QPI 1.4

Dram volts 1.54

 

rest of everything is on AUTO and HT is also OFF /Turbo is also OFF

on these settings my i7 950 @ 3.7GHz is stable more then 10 hours in prime95 blend test and NO errors but when i try to overclock my cpu to 4 GHz its even not stable @ 1.33v

 

the settings i used for OC it to 4 GHz is same as above except Dram is running @ 1750 MHz and even its not stable if i run the ram @ 1450 MHz.even increasing / decresing Multi & Bclk is not stable @ 4ghz on 1.33v.so why my i7 950 requires such a high increase in CPUVTT from 3.7GHz to 4GHz.

3.7GHz stable on 1.22v while for 4GHz it take more then 1.33v.why is this?

[AIinc]

It might be your memory's timings?

 

Try 8-8-8-26

 

It's not going to affect your performance by setting it to 21, but can be the cause of your instability.

[ccokeman]

Looks like you found the problem in your sig. QPI to 1.4 helps