2600k Undervolting help

[[XC] flat-four]

So I just upgraded to a 2600k and am stuck using the stock heatsink until finals are done and I have time to put my watercooling loop back together. Does anyone have any advice for undervolting? I've read some people recommend using offset voltage instead of a static voltage. Temps are a little high for my tastes (around 79 fully loaded). Thanks!

[shoota]

Post which board you have. I think you can use the offset voltage to create a negative delta which should decrease from the stock vcore. Then you could set your desired multi and lock that in. I'm no pro and I just regurgitated what I've just learned in the past day but that should be a good start

[Manicdan]

i concur, offset voltage is awesome, and i use it with LLC to help make a bigger difference between idle and load, right now its about 25 or 50% so my idle is .98v and load is 1.35 and my offset i think is set to some stupidly low amount like .05, since 0 = auto and added some crazy volts based on clock rates.

(for the asus maximus gene m-atx)

[Tom128]

Here I was thinking you COULDN'T set a static CPUv for SB chips. I got my 2600k a bit ago and I don't have a setting for CPUv, only for an offset unless I am missing something. I can basically set any voltage I want, I just have to leave it at +-0 and check what the CPU picks at a given multiplier and then change it from there.

I need to read up on overclocking Sandy's more lol. This was my first non-AMD chip since my Pentium III so I know very little of the details, I may well be missing how to set a static CPUv. Most annoying part is that CPUz always shows my CPUv at 1.0v regardless, CoreTemp seems to give a better number though.

[shoota]

Here I was thinking you COULDN'T set a static CPUv for SB chips. I got my 2600k a bit ago and I don't have a setting for CPUv, only for an offset unless I am missing something. I can basically set any voltage I want, I just have to leave it at +-0 and check what the CPU picks at a given multiplier and then change it from there.

I need to read up on overclocking Sandy's more lol. This was my first non-AMD chip since my Pentium III so I know very little of the details, I may well be missing how to set a static CPUv. Most annoying part is that CPUz always shows my CPUv at 1.0v regardless, CoreTemp seems to give a better number though.

You might try Gigabyte's EasyTune6 software. I think it might have what you are looking for. I'll install it right now and see actually. *Edit: Yep it's got all the goodies.*

[shifty803]

Yeah I could swear mine doesn't have the ability to set a static vcore in the BIOS. I am running a Z68 Gigabyte board. Could have missed it... or maybe you're supposed to use EasyTune? Either way, my overclock has a ridiculously low voltage (using offset) for the clock speed, so I'm happy. My last board was a P6X58D Premium, and this one is about the cheapest Z68 board you can get. Cheapness didn't seem to matter for mid-range overclocks one bit.

Edit: This is all ET6 will give me (this is at full load, 8 threads) - seems to be just dynamic vcore. I did all my overclocking in the BIOS though.

[Otis11]

Yeah I could swear mine doesn't have the ability to set a static vcore in the BIOS. I am running a Z68 Gigabyte board. Could have missed it... or maybe you're supposed to use EasyTune? Either way, my overclock has a ridiculously low voltage (using offset) for the clock speed, so I'm happy. My last board was a P6X58D Premium, and this one is about the cheapest Z68 board you can get. Cheapness didn't seem to matter for mid-range overclocks one bit.

Edit: This is all ET6 will give me (this is at full load, 8 threads) - seems to be just dynamic vcore. I did all my overclocking in the BIOS though.

You might want to drop your PLL voltage. I put mine down at 1.52V.

Also notice your RAM is high... you might need it there but mine, even though it is rated at 1.65V runs well at 1.55V.

Other than that looks great! Got any power numbers by chance?

[shifty803]

Very good advice about the PLL voltage otis. I looked into it a bit, because the guide I used did not mention it. Check out this post here:

http://www.overclock.net/t/968053/of...#post_14658240

Seems that lower PLL improves stability for alot of people, which is very counter-intuitive to me.

Edit: Sorry, no power numbers. I will probably buy a kill-a-watt once I move into our new place in a couple weeks. Stand by I guess.

[shoota]

Yep I definitely have vcore adjustment. Anyhoo, what suggestions do you guys have after seeing these settings?

[shifty803]

You should be able to run low PLL voltage, like 1.52 at least. Seems it actually helps stability. Try lowering vcore as much as possible, and that is about it. Just lower by like 0.01 or 0.025 increments until you aren't stable, then bump it back up.

[Otis11]

You should be able to run low PLL voltage, like 1.52 at least. Seems it actually helps stability. Try lowering vcore as much as possible, and that is about it. Just lower by like 0.01 or 0.025 increments until you aren't stable, then bump it back up.

This. Lower that PLL and it'll allow you to get a lower Vcore. At 4.3 Ghz I'd be expecting 1.28v ish... am I way off on this? Mine did up to 4.5 on 1.32... and iirc 1.27 on 4.2...

I agree - seems counter intuitive, but it works.

[shoota]

Right now I'm at 4.2, 1.275 vcore, 1.54 pll. Stable so far but I guess I didn't get a great clocking chip..

[Otis11]

Right now I'm at 4.2, 1.275 vcore, 1.54 pll. Stable so far but I guess I didn't get a great clocking chip..

No that sounds about right - now just gotta dial it in and see what helps.

Some chips like if you put them at 99 Bclk instead... can sometimes get an extra multi at same Vcore...

What else... been a while since I did mine...

[shoota]

Yeah good trick I'll try that. Is there any possibility that overclocks will vary between boards?

[Tom128]

I guess my board just does not have a static CPUv. I have ET6 and where you have CPU Vcore under system Agent, I have Dynamic Vcore. Either way I can still control the final voltage so I don't care.

My chip takes 1.3v for 4.2Ghz it seems, but I have barely done any tweaking. My CPU PPL is at 1.8v at well, the default I guess. I will see if lowering that to 1.52v lets me get a higher clock at this voltage.

[bluestang]

This is what I did for my GA-P67A-UD4-B3 and 2600K setup....

I'm using F5 BIOS and I'm relying on the SVID and VRD12 system to work together like it should when I increase my multi.

I have all of the following either off or disabled:
XMP
Real Time Ratio Change in OS
Turbo Boost
C1E, C3/C6, EIST (this is important)
LLC

Internal PLL Voltage is enabled, HT On, CPU PLL at 1.70v, DRAM at 1.60v and all other volts an Auto.

With this my voltages set for me by SVID (CPU Vcore=Auto) it works out to this (Multi / BIOS / CPU-Z idle / CPU-Z load):

34x / 1.200 / 1.176 / 1.176 / didn't bother looking
38x / 1.315 / 1.284 / 1.284 / didn't bother looking
40x / 1.320 / 1.284 / 1.284 / didn't bother looking
45x / 1.340 / 1.308 / 1.308 / 1.248-1.260 (Prime/LinX/WCG Stable) highest core temp 58C (25C ambient)

4.5 GHz at 1.260v load is pretty darn good if you ask me.

Let the MB, BIOS, and CPU work together for you and see what happens.

[[XC] flat-four]

Thanks for the help guys. I've decided to stay with the offset enabled rather than have a static voltage until I decide to start overclocking. My motherboard has a utility called Intelligent Energy Saver that at 3.6 ghz, vcore is set at 1.08 with temps around 72 degrees. I'm comfortable with those temps for a few weeks till I can get some watercooling set up.

[Otis11]

That temp seems high for such low voltage... you have enough case ventilation?

I'm looking at 72C on stock (need to get a cooler over break to OC this thing) but my ambients are 73F and an open case...

[shifty803]

Just pick up a cheap coolermaster hyper 212 EVO or something along those lines. You will easily be able to do 4+ GHz I would imagine without raising voltage/temps too much.

[Otis11]

Just pick up a cheap coolermaster hyper 212 EVO or something along those lines. You will easily be able to do 4+ GHz I would imagine without raising voltage/temps too much.

Planning on getting a H70/80/100 or something along those lines if I can find one for cheap... Want to crank it as high as I can stably get it - max pointage. For me efficiency matters less than initial cost at this point. (I know, I know, but trust me on this one...)

Edit: anyone have any experience with the Antec Kuhler H2O 620?

[shoota]

Looks like a decent cooler but you could probably do just as good with a TRUE or similar, and maybe cheaper too.

[Otis11]

Looks like a decent cooler but you could probably do just as good with a TRUE or similar, and maybe cheaper too.

This computer will get moved a lot, and seeing as it's predecessor died when the HS cracked the mobo in the back seat of my car I was trying to steer clear of the big metal ones...

[shoota]

Oh that changes everything. I'm sure it's a fine cooler. The reviews all seem decent enough.