Hi, this is my first time overclocking, and it has been a very frustrating experience . My goal is 3.6, which seems to be a very common speed for overclockers using E6750. Here's my specs:
Intel Core 2 Duo E6750@2.66Ghz(333*8) 1333fsb
Gigabyte P35-DS3R BIOS F4
Crucial Ballistix 2x1Gb PC6400 4-4-4-12@2.2V
Cooler Master extreme power 500W PSU
Cooler Master GeminII CPU heat sink
EVGA superclocked 8800GTS 320MB @578mhz
Maxtor 500GB SATAII HDD
Lite-on 20x DVD+/-RW SATAII
Antec solo case

At stock speed, the processor runs at around 1.3V, idle 19C, load 35C
I first I tried to overclock it to 3.6Ghz (450*8), increased voltage to 1.55V, and set ram timing to 5-5-5-15. Prime95 failed after 2 seconds .
Then I decreased my CPU clock to around 3.4Ghz (425*8), keep the same 1.55 voltage, idle 28C, load 48C, failed after around 2 minutes .
I decreased my CPU clock down to 3.2Ghz (400*8), voltage down to 1.4V. Failed after 8 minutes.

Do you know what's happened there? I looked at other people's specs and they seemed to be able to get to 3.6Ghz at 1.35V or even less. And if you are familiar with Gigabyte P35-DS3R and Ballistix memory, is there any special settings required for them to work at high clock speeds? For example, I have no idea what setting I should set for FSB overvoltage, etc. Thanks a lot!

I wouldn't play with the voltages imediately, see how far you can stick the fsb up to on stock voltage. Then increase the fsb still it destabalises then added like 0.05v to stabilise, rinse and repeat. You don't need an extra 0.2 volts which is quite a lot and is the reason for your crashes. There is a reason why some mobos have 0.0125v increments in their bios. Good luck.

What's your memory speed? What is the multiplier? Use CPU-Z.

First off for 3.6 you will need to set Vcore to 1.47 Your MCH and FSB overvolts to +.1 Leave all other overvolts in manual. Ram divider I have set at 2 (1:1) and had to add .3 because gigabyte defaults at 1.8v. Run orthos Not all C2D's are the same you might get stable at 1.41 Vcore I know others that have but most are at 1.47.

Radion:

Ive got mine running 3.4 @ 1.45vCore +.2 FSB and MCH +.3memory (2gb crucial ddr2-1066 running 900 for 1:1)

when i bump mine to 3.6 it crashes once windows boots.... if i up it to 1.475 it crashes 1 min into prime95...

any reason why this last bit of 200MHz is requiering so much more juice? or should I be raising the MCH FSB to +.3?

(I could only get it to run prime95 @3.6 running a 1.525vCore but temps were up in the high 60's *~68)

p35-ds3r
e6750
thermalright 120extreme + silenX fan

Just go bit by bit. Crank it up little by little at stock voltages then if you need to up the voltage do it.

Voltage requirements become exponential.

As an example..

At 1.248 vCore my Quad can run up to 3.0 GHz.
At 1.264 vCore it can run up to 3.3 GHz.
At 1.312 it will run 3.4 GHz.
Needs 1.4+ to hit 3.5 or 3.6.

ah, thanks,

But have you heard of anybody needing 1.5+ vcore to hit 3.6 on the 6750's? It seems nearly 100% of posts i Read are below even 1.47. Just trying to figure out if it could be something else crashing my system like FSB voltage or something. My memory is 1066 so I would assume it is not the culprit since I am only running it at 900.

Drop the CPU Multi to like 6 and run the tests at the same Bus.

If it runs fine, it's not the NB.