Manual vs offset voltage

[funkatation]

Fellow SB'ers, which setting are you using to set your vcore? I found that if I used manual that when the cpu would clock down to 1600 mhz, the voltage did not go down with it. If i used offset, it would lower the voltage on idle.

Some observations I've seen when using offset:
If I set it to Auto, the voltage used can be very erratic, I've seen as high as 1.35V! I've set my multiplier to 42 and it was much higher than I thought it should be. I put the offset at -.070 and under load it doesn't get any higher than 1.2V. Temps went up 1-2C with the 4.2Ghz overclock. Definitely very happy with that, but just very concerned over this manual vs offset voltage! I have LLC set to Auto.

I have a Sabertooth P67... saw similar results with the P8P67 I had.

 

[tweakboy]

Turn off SpeedStep in BIOS, also disabled C1E also in the BIOS, and your problem is fixed.

 

[DrBoss]

i am also quite interested in this subject, as i am experiencing the same issue (with the same mobo).

Unless you are purely going for the ultimate overclock it seems disabling C1E and SpeedStep is generally not advised.

 

[Lightflash]

You will be better off not disabling C1E and SpeedStep with the S1155 unlike with the previous generation as DrBoss said.

I would suggest setting the voltage manually for your overclock as most auto settings will go much higher than necessary and SB is more worried about voltages instead of temperatures. I would suggest finding the best voltage by going up by the lowest increments of the Sabertooth until it runs stable.

As for high idle voltage, each company has different names for the lower idle voltage settings. I believe MSI is CPU I/O Voltage, or at least that is what my mind is telling me right now without being in front of my computer.

 

[funkatation]

Thats the problem with setting the voltage manually, it doesn't change at all when it idles/downclocks. If I use "offset" it does, but I haven't seen a real clear indication what offset actually means. I have it giving the desired result I want (1.2V), but I really have no idea how it does it, if that makes sense. If I have it set to an offset of -.070, that would mean the "non offset" voltage is 1.270, which to me seems wrong because the stock voltage should be 1.2 IIRC.

 

[Accord99]

The offset value is added (or subtracted) from the voltage that the MB would have otherwise provided based on the CPU load, number of cores loaded and LLC setting. So the measured voltage can change depending on how intense the load is (Prime95 will draw down the voltage more than a game), how many cores are running (fewer cores will result in lower voltage) and the LLC setting (which will try to minimize the voltage drop when running more intense loads but also result in lower voltages at idle and low load situtions).

The main challenge with the offset method occurs at the higher overclocks, at like 4.7 GHz or higher, because you need to ensure that the voltage doesn't too low at intense CPU loads, isn't higher than necessary at typical loads and doesn't drop too low when one one core is running and when at idle.

 

[DrBoss]

shame we are unable to simply set the LOAD voltage independently.

 

[tweakboy]

wtf
I disagree keep C1E and SpeedStep OFF

now go to BIOS defaults and reset everything and dont OC ,, lets see what happens. gl


sorry bossman

 

[Termie]

The offset value is added (or subtracted) from the voltage that the MB would have otherwise provided based on the CPU load, number of cores loaded and LLC setting. So the measured voltage can change depending on how intense the load is (Prime95 will draw down the voltage more than a game), how many cores are running (fewer cores will result in lower voltage) and the LLC setting (which will try to minimize the voltage drop when running more intense loads but also result in lower voltages at idle and low load situtions).

The main challenge with the offset method occurs at the higher overclocks, at like 4.7 GHz or higher, because you need to ensure that the voltage doesn't too low at intense CPU loads, isn't higher than necessary at typical loads and doesn't drop too low when one one core is running and when at idle.

I don't know if SB is different, but on 1156, the problem with offset (which I use), is that it's based on what the motherboard would deliver automatically, and if that's too high, which it often is once you overclock, you need a negative offset. But that messes up the idle voltage, which will now drop too low (I'm not familiar with a separate setting for idle voltage, which LightFlash suggested - maybe that's an SB thing).

In somes cases, I'd say using automatic voltage is still preferable to setting a manual fixed voltage, because while you're using more power than necessary at load, you're using way less at idle. If you are at load 24/7, however, temps would start to become a problem with the auto method, and in this case, a fixed voltage would be best (since there's no idle to worry about).

 

[DrBoss]

wtf
I disagree keep C1E and SpeedStep OFF

now go to BIOS defaults and reset everything and dont OC ,, lets see what happens. gl


sorry bossman

ok, here is what i will do. i will go home and turn those off, input my manually set 1.2v, 4Ghz OC, boot and wait to see the Vcore drop when the computer is idle... which i doubt it will do considering that processor function is governed by SpeedStep.

by all means tell me why i am wrong in this assumption or please explain why C1E and SpeedStep should be turned off.

 

[Termie]

ok, here is what i will do. i will go home and turn those off, input my 1.2v 4Ghz OC, boot and wait to see the Vcore drop when the computer is idle... which i doubt it will do considering that processor function is governed by SpeedStep.

by all means tell me why i am wrong in this assumption or please explain why C1E and SpeedStep should be turned off.

DrBoss - I think the consensus is that this isn't good advice. But for a q6600 at 3.7, which is what TweakBoy has, it probably makes sense.

 

[Rvenger]

DrBoss - I think the consensus is that this isn't good advice. But for a q6600 at 3.7, which is what TweakBoy has, it probably makes sense.

I also have Speedstep and C1E off. But I have C-State set to "No Limit" Sorry to thread jack but what is the difference b/w C1E and C-State?

 

[DrBoss]

I also have Speedstep and C1E off. But I have C-State set to "No Limit" Sorry to thread jack but what is the difference b/w C1E and C-State?

With those settings does your Vcore throttle down in idle conditions?

Can't answer your question, as i am pretty unfamiliar with SB architecture/functions.

 

[tweakboy]

ok, here is what i will do. i will go home and turn those off, input my manually set 1.2v, 4Ghz OC, boot and wait to see the Vcore drop when the computer is idle... which i doubt it will do considering that processor function is governed by SpeedStep.

by all means tell me why i am wrong in this assumption or please explain why C1E and SpeedStep should be turned off.

Depends on user and their needs.

 

[d4a2n0k]

P67 is different. Enable C1E, speedstep and offset and then your voltage will drop when idle, as the OP mentioned if you put it in manual, the voltage stays where you set it. You definitely want the voltage to drop when idle.

 

[DrBoss]

P67 is different. Enable C1E, speedstep and offset and then your voltage will drop when idle, as the OP mentioned if you put it in manual, the voltage stays where you set it. You definitely want the voltage to drop when idle.

Is that C1E, Speedstep and Offset enabled with cpu voltage set manually?

 

[Diogenes2]

You just have to experiment with offset to see what it takes to get your stable highest overclock ..

I ended up with + .135 to end up with about 1.44 when running 4.9g .. Drops to 1.0 when idle at 1.6g...

 

[Termie]

You just have to experiment with offset to see what it takes to get your stable highest overclock ..

I ended up with + .135 to end up with about 1.44 when running 4.9g .. Drops to 1.0 when idle at 1.6g...

Out of curiousity, does that offset affect your idle voltage, i.e., would it it be 1.0v at stock, or would it be more like 0.865v?

 

[Rvenger]

P67 is different. Enable C1E, speedstep and offset and then your voltage will drop when idle, as the OP mentioned if you put it in manual, the voltage stays where you set it. You definitely want the voltage to drop when idle.

I did the same as you said and all my voltages stay the same. I don't have the offset voltage option and I am on an MSI P67A-C43.

 

[Accord99]

I don't know if SB is different, but on 1156, the problem with offset (which I use), is that it's based on what the motherboard would deliver automatically, and if that's too high, which it often is once you overclock, you need a negative offset. But that messes up the idle voltage, which will now drop too low (I'm not familiar with a separate setting for idle voltage, which LightFlash suggested - maybe that's an SB thing).

Sounds like the behavior is the same; you see this often too where people with Sandy Bridge are stable with Prime 95 but crash when running games or even idling as the idle and low-load voltage end up being too low. The P8P67 series did add a new option where you can add additional voltage for Turbo, which generally allows the use of a lower offset and lower idle but it still takes a lot of fine tuning with LLC, offset and Turbo voltage settings to get a balanced voltage in all situations.

 

[d4a2n0k]

Sorry, dont have any experience with MSI. With ASUS, you choose Offset mode instead of manual and you can choose + or -. Stock voltage is 1.18 so if you wanted about 1.25v you would set it as + and .07v. Ive used a P6P67 Pro and a Maximus IV Extreme and both would lower the voltage when at idle. In manual mode it would not.

 

[Diogenes2]

Out of curiousity, does that offset affect your idle voltage, i.e., would it it be 1.0v at stock, or would it be more like 0.865v?

According to HW monitor my minimum is 0.89, but I've never really observed it that low..

 

[Termie]

According to HW monitor my minimum is 0.89, but I've never really observed it that low..

Very interesting. Looks like SB is pretty good about getting voltages down in idle even with an offset, but that it does more active adjustments (which others have pointed out as well), so it's never one set voltage for very long.

 

[Hogan773]

According to HW monitor my minimum is 0.89, but I've never really observed it that low..

I am minus .05 on 42x on 2600k and at idle I am around .86-.9

Never crashed yet

For all those who say to turn off C1E and Speedstep, I think you're living in the past.

 

[funkatation]

really strange how the offset can vary so much from chip to chip!