with a low VID of 1.21v on my Q6600

[core2slow]

BIOS vcontrol set to 1.33v
CPUZ idle @ 1.26v, load @ 1.20v...temp idle @ 33c, load @ 55c
mem @ 1.85v (1.8v-1.9v as suggested by G.Skill)

Right now im stable at 3.3ghz, but a few hours into small FFT @ 3.4ghz, i get BSOD. What's the likely culprit that's holding me back?

 

[Idontcare]

Even with low VID you will need to start ramping up that Vcore to score each 100MHz gain over 3.3GHz.

Also you will likely need to pay attention to your NB/MCH voltage as well as FSB termination voltage as you up that FSB.

My DS3L has no issue going to 9x367 with G0...but it really balks at going any higher.

That stock NB passive heatsink doesn't help either. For kicks you should touch it while your 3.3Ghz G0 is fully loaded on blend or large FFT. It's a sizzler.

 

[core2slow]

Originally posted by: Idontcare
Even with low VID you will need to start ramping up that Vcore to score each 100MHz gain over 3.3GHz.

Also you will likely need to pay attention to your NB/MCH voltage as well as FSB termination voltage as you up that FSB.

My DS3L has no issue going to 9x367 with G0...but it really balks at going any higher.

That stock NB passive heatsink doesn't help either. For kicks you should touch it while your 3.3Ghz G0 is fully loaded on blend or large FFT. It's a sizzler.

D'oh! I knew i forgot to do something with the NB/MCH. Right now i have them all at +1v (DDR2, FSB, PCIE, MCH), should i bump MCH up to +2v then? what else should i ramp up other than vcore and mch? Thanks.

Oh and to address the ventilation of the NB, I have 3x120mm blowing right at it.

 

[Idontcare]

Yeah you could try to set the voltage to +0.2.

And Vcore will need a bump too.

Here is real data plotted for my B3 QX6700...albeit frozen at -40C by vaporphase cooling:

http://i272.photobucket.com/al...ableVcoreversusGHz.jpg

That's the prime95 small FFT required voltage versus clockspeed plotted there. Note how that thing is really clicking upwards thru the voltage ticks once I get out >3.2Ghz?

And that isn't thermal limited at all, just brute force voltage needed to flip those xtors. If I had it on air and required more Vcore to overcome the operating temps then you could imagine how much higher the required Vcore would be as I scaled >3.2GHz.

I should have made one of these graphs for my G0's on air...just never got around to it.

 

[EarthwormJim]

VID isn't a complete indicator of overclocking potential, nor is it s predictor of what voltage will be needed at xx speed.

If it helps though, my X3210 (quad core G0 stepping) with a 1.225 VID (fairly low like yours) needed 1.3v actual to get to 3.4ghz. 3.6ghz needed 1.35v actual and 3.8ghz needed 1.41v.

Those are all readings from CPUZ, not what I have my bios set to.

Intel certifies you to go 15% over your VID, so stop being so conservative with your voltage.

 

[core2slow]

Originally posted by: EarthwormJim
VID isn't a complete indicator of overclocking potential, nor is it s predictor of what voltage will be needed at xx speed.

If it helps though, my X3210 (quad core G0 stepping) with a 1.225 VID (fairly low like yours) needed 1.3v actual to get to 3.4ghz. 3.6ghz needed 1.35v actual and 3.8ghz needed 1.41v.

Those are all readings from CPUZ, not what I have my bios set to.

Intel certifies you to go 15% over your VID, so stop being so conservative with your voltage.

I'm assuming that its stable after a few hours of Prime?

Originally posted by: Idontcare

I should have made one of these graphs for my G0's on air...just never got around to it.

you definitely should!

 

[Sentry2]

Man, I wish I had a 1.21v VID chip...I need 1.55v(actual) or better for complete stability @ 3.762GHz.