Been I while since I've tinkered with my setup but I got a shiny new GTX980 today and was tweeking my settings in prep over the weekend...
I've now landed on what seems to be a stable 4.2GHz overclock using air cooling. As mentioned in earlier posts, my cooling is an older design Noctua NH-U12P SE2 but with some of the newer PWM focused flow fans bolted on. Also using some MX-2 thermal paste for the heat sink as well.
Anyhow what is very pleasing is that I'm achieving 4.2Ghz with only 1.288 volts on the VCore. As a result I'm seeing my temps holding pretty low (Ideals around 33 - 34C on one core and the rest between 27 and 31C ish). As mentioned in my earlier posts here, I've got a X5675 so have the advantage of multi up to 25. This means I am using a lower Bclk of 168Mhz to get to 4.2Ghz which I think helps keeps the overclock stable.
I've also kept the QPI volts low at ~1.288 as well, but did have to step down the QPI frequency from the highest speed setting to the middle setting giving a QPI Link speed of 3695Mhz (Displayed in CPUZ). I wasn't able to get my system to boot successfully even with some extra volts pumped into the QPI when it was on that highest speed setting. I gave up adding QPI volts after getting to 1.3 cause it didn't seem to be making any difference and I figured a +4Ghz QPI Link speed was just too high a frequency especially with all 6 RAM slots populated on my board. Once I stepped the QPI link speed down a notch it has been fine booting and running Windows.
I've had a 10 run Intel Burn Test complete with these Bios setting using a "custom" IBT test config for 9655meg of ram and saw max temps of 76c. Ambient temp in my room was 21c when I started the test. I find IBT crashes my system if I run it on Max setting to use all my available RAM (~24 Gigs). I recall reading somewhere it has a bug when run with a config over 10Gig of ram. Does anyone else know \ has heard about that issue with it?
I'm thinking of installing Cinebench to see how my system as a whole gets rated. I'll report back once I've got that sorted and run a test.
On a side note I'm having trouble uploading screenshot images here for some reason... Is there something special I need to do?