Q6600@3.6ghz prime95-cores failing

Heyy guys.
So I went from 3.4ghz to 3.6ghz and my cores on prime95 are not stable.....I use zerotherm nirvana heatsink so temps are not a problem....
In bios I set fsb to 400x9 giving me 3.6ghz
oh and vcore is at 1.5v (1.496 in cpuz)
the bios will not let me go over 1.5volts,
so when I start prime95 core 1,3,4 fail and after a minute core 2 fails.....
my system specs are as follow

*G.Skill 4gb ddr2 800
*Vista 64bit
*Intel Core2Quad q6600 @ 3.4ghz ( 3.6ghz plx? ;/////)
*Antec TwelveHundred full tower case
*Silverstone 700w modular striker series
*ZEROtherm Nirvana cpu cooler
*Power Color Ati 4870 1gb ddr5 edition (800core/1090memory)
*ASUS 20X DVD±R DVD Burner
*Seagate Barracuda 500gb HD (2x)
*P45 ASUS P5Q SE
*Acer 22"


please give me your thoughts why my cores fail
thanks!
 

w153r

Distinguished
Feb 2, 2007
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I have my g. skill ddr2-800 @ 1000mhz 2.2V, and my q6600 @ 3.6ghz 1.4V. I bumped my FSB +.3.

q6600_24_7_settings.jpg
 

javimars

Distinguished
May 16, 2006
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nice job on the oc. if you have this ram :Module Name G Skill F2-6400PHU1-1GBHZ you can run them at 1200mghz but at very loose timings and 2.3volts. i have similar build but i fried one of my memory modules and only have 3gigs at the moment. i also believe one of my remaining modules is damaged as i can no longer have such a high oc. i run mine at 3.4ghz but if i do prime95 it will crap out due to the memory. many people with same memory have the modules die after a year. don't get me wrong they are amazing chips but if you can go for pc2 85000 ram, you will have a greater overclock and stability.