e6600 undervolting...

AndeeG · Post by **AndeeG** » Thu Jul 12, 2007 12:48 pm

I'm pretty new to the whole overclocking/undervolting, etc. scene so I'm not quite sure how one would go about doing either - undervolting in particular. Is it as simple as going into my BIOS, selecting a lower voltage, and then running some stress tests to see if it's stable? I was just looking at Palindroman's thread and he made it seem like some other undervolting software was necessary.

jaganath · Post by **jaganath** » Thu Jul 12, 2007 2:26 pm

Is it as simple as going into my BIOS, selecting a lower voltage, and then running some stress tests to see if it's stable?

yes,if BIOS has voltage options. The undervolting s/ware is for if you don't have BIOS voltage control or want to create more sophisticated u/volting scheme (ie EIST but w/ lower voltages/higher clock speeds).

lm · Post by lm » Thu Jul 12, 2007 5:36 pm

The stress testing is pretty important part of it.

For me to consider a system stable, it needs to pass 24h of prime95 and memtest86, and then ease the settings one notch.

AndeeG · Post by **AndeeG** » Fri Jul 13, 2007 1:36 pm

Alright, well that seems pretty straightforward. What would be a good starting voltage to try? I think my mobo voltage control goes down to maybe 1.15 or so. Also, what stress tests should I be running. I've heard that orthos is good, and lm mentioned prime95 and memtest86.

merlin · Post by **merlin** » Fri Jul 13, 2007 3:55 pm

AndeeG wrote:Alright, well that seems pretty straightforward. What would be a good starting voltage to try? I think my mobo voltage control goes down to maybe 1.15 or so. Also, what stress tests should I be running. I've heard that orthos is good, and lm mentioned prime95 and memtest86.

At stock speed most e6600's will probably be stable at 1.15v. I know mine can easily drop to 1.1v and probaby lower..however I've not done heavy stress testing yet. I'm personally in the process of finding the right balance between overclock and undervolt. Currently it's putting me at 3.0ghz at 1.2v...but that's subject to change as I tweak things. I would just set it directly to 1.15v and do the 24 hour prime95(on both cores) and anything else you like at the same time. Normally if you're trying for max undervolt, you'd chase after some insanely low voltage such as .9v, test that and then move up to something a bit safer such as 1.05 to give yourself cushion. However it sounds like anything under 1.15 will require software to tweak your voltage.

nd4spdbh · Post by **nd4spdbh** » Fri Jul 13, 2007 8:51 pm

i got my E6600 at the lowest voltage my mobo (asus p5w dh) will supply 1.225v... and i have her clocked at 3.0ghz fully stable! and temps are super nice also even with a ultra 120 and a yate loon @ 5v

Palindroman · Post by **Palindroman** » Sat Jul 14, 2007 12:25 am

I would just set it directly to 1.15v and do the 24 hour prime95(on both cores)

In my experience Orthos is a much easier to use stress testing program for dual cores. You have to perform a trick with the command line for Prime95 and with my 3600+ it didn't work. With Orthos you just press one button and you're off.

Undervolting with RM Clock really isn't too difficult, AndeeG, and much handier than undervolting your board. When you undervolt your board it stays at that voltage, whatever the clockspeed. With RMClock you get a dynamic voltage and clock speed, which means your CPU works like an automatic gearbox. It's quite straightforward if you put a bit of time in it. I'm no computer expert, but I got the basics in no time. Read the tutorial that I mentioned in my thread.

And mention your results if you decide to use RM Clock. Good luck!

jaganath · Post by **jaganath** » Sat Jul 14, 2007 4:33 am

which means your CPU works like an automatic gearbox.

unfortunate analogy,auto box is less efficient than manual

AndeeG · Post by **AndeeG** » Sat Jul 14, 2007 12:11 pm

@ Palindroman: If I use RM Clock to undervolt, does it matter what I set the voltage at in the BIOS? Will RM Clock just override whatever that setting is?

Also, with regards to power usage and heat production, is voltage the only factor or does clock speed make a difference? If I have my CPU running at 2.4ghz and 1.2 volts, will that use less power than it would at 3ghz but still 1.2 volts?

cmthomson · Post by **cmthomson** » Sat Jul 14, 2007 8:12 pm

RMClock changes the settings once Windows is up. In other words, yes, it does override the BIOS settings. This is good: you can set the BIOS to something conservative that will always boot, then set RMClock to something more aggressive.

The power consumption of a CPU is V*V*F (ie, linear with the clock speed and with the square of the voltage), so lowering the voltage has a much more dramatic effect on power consumption than lowering the frequency.