Stable E8400 OC - stock voltages

[Chike]

Re: Stable E8400 OC - stock voltages

vtt = CPU termination.
Both reference voltages are relative to vtt and drived from it.

Your current MCH Ref is [email protected] so that is like [email protected], change vtt to 1.2 and see what is the MCH Ref is changed to.

As I said the reference voltages are percent of vtt. Sadly it's not how it is represented in BIOS like it is in the X38/X48 boards, which would cause much less of confusion and simplify the way to set them.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

vtt = CPU termination.
Both reference voltages are relative to vtt and drived from it.

Your current MCH Ref is [email protected] so that is like [email protected], change vtt to 1.2 and see what is the MCH Ref is changed to.

As I said the reference voltages are percent of vtt. Sadly it's not how it is represented in BIOS like it is in the X38/X48 boards, which would cause much less of confusion and simplify the way to set them.

I find that confusing. LOL. So I'm at .785 MCH Ref with 1.24v CPU Term. CPU Term is VTT (whatever VTT stands for) correct? But I'm actually not? It actually equals .76 Mch Ref and 1.2 CPU Term instead? How do we arrive at that? (maybe I haven't had enough coffee yet) Is that like saying 4/8 equals 1/2? And since we think it's really 1.2 CPU Term I should drop it to that value and see what happens to MCH Ref? This makes no sense. For me those are manual settings. They don't just randomly change. As in change one and another setting gets changed. Unless people are finding out the BIOS settings are simply wrong and equal something else.

Where else can I go to see these readings if not in the BIOS? Any software I have doesn't really show this. Some but not what we're talking about.

By the way the "Normal" settings for my mb with f/w F7 for CPU Term is 1.2v and the MCH Ref is .76v.

[Chike]

Re: Stable E8400 OC - stock voltages

Is that like saying 4/8 equals 1/2?

Exactly that. Default CPU Ref is .063333...(63%) of CPU Term, and as long you don't change it it remain 0.63333. If it was like that in BIOS you would be told simply to set it to .62 or 0.63 or whatever, since it's not, and you can't expect people to remember all reference values for all vtt values, vtt 1.2 is used as point of reference.
If you understand this you don't have to drop to vtt 1.2 change them and set it back to current value.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

Sorry guys. I'm a visual learner and having a tough time with this. I'm sort of getting it but it's not clear. I'm not sure what to adjust to what and how to verify what I'm actually getting and then what to set it to. Right now it's about as clear as mud. I hate to say it but I need to find someone available to walk me through this process.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

Anyone? I think we're really close.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

Exactly that. Default CPU Ref is .063333...(63%) of CPU Term, and as long you don't change it it remain 0.63333. If it was like that in BIOS you would be told simply to set it to .62 or 0.63 or whatever, since it's not, and you can't expect people to remember all reference values for all vtt values, vtt 1.2 is used as point of reference.
If you understand this you don't have to drop to vtt 1.2 change them and set it back to current value.

So do you recommend I change the MCH Ref (now .76/default)?

[BoombasticSloth]

Re: Stable E8400 OC - stock voltages

Yes, drop your mch ref down one notch, and test for stability. If that doesn't help, then try one more notch down and test. Enter what you have tried into the spreadsheet I gave you so that you know what you have done, and whether the bios setting that was changed helped or not. For example, drop your mch ref to 0.74v when vtt was at 1.20v, then increase your vtt back to 1.24v. You will notice the mch ref value increase 2 notches to .... I don't know... 0.775v +- or whatever, I can't remember exactly. Test for stability. If it errors, note duration of time before prime fault, bsod, or IBT results (Gflops, temp, etc.). If it primed longer than when mch ref was at 0.785v, then the change that you did, probably helped. And so on, get it?

Just do it. Things will start to make more sense.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

For example, drop your mch ref to 0.74v when vtt was at 1.20v, then increase your vtt back to 1.24v. You will notice the mch ref value increase 2 notches to .... I don't know... 0.775v +- or whatever,

I appreciate your responding.

But within this information is where I'm getting a little lost. Adjusting the MCH Ref down is not an issue. I know my default MCH Ref is .76v (where I currently have it set). So dropping it to .74v is fine. I get lost when I'm being told "drop your mch ref to 0.74v when vtt was at 1.20v, then increase your vtt back to 1.24v. You will notice the mch ref value increase 2 notches to ...." Where am I suppose to see the MCH Ref increase and apparently on it's own? In ET6? I'm NOT seeing this happen in the BIOS.

I had also adjusted the "Static tRead Value" from 11 to 10. I imagine it's best to adjust them back to 11 until I get stable with the MCH Ref before making any other adjustments?

[Chike]

Re: Stable E8400 OC - stock voltages

This is pretty strait forward, the how without the why.
To set CPU/MCH Ref above or below default, set vtt to default which the default refs for are known, set it above of below default as desired, set vtt back to it's original value.
Csn't make it more simple than that.

[Psycho101]

Re: Stable E8400 OC - stock voltages

I'm NOT seeing this happen in the BIOS.

You must be seeing it, it's a certainty. I can understand however that if not 100% familiar with things you can miss it.

TO see MCH Ref scale up as you change VTT (CPU Termination) do the following:

Set VTT to 1.20V
Set MCH ref to your new desired value, so for now type 0.740V
Use the arrow keys to go back up to the CPU termination setting.
While pressing page up and page down (to increase and decrease CPU termination) watch the numerical value of MCH ref.

You will then clearly see that as you increase CPU termination, MCH Ref will also go up. As you then decrease CPU Termaination, you will see it go back down.

You seem to be an alert kind of chap and have shown willing to learn which is good. You now must get stuck in and get some settings tried. As BoombasticSloth says, you eed to experience how things you change effect your PC. Be a little more confident. You're now armed with all the knowledge you need. It's time to make a concentrated effort to put it all together. I know you have only a small amount of time to dedicate to this, so it's best to make your time spent count.

At this stage, there's not really any more info anyone can give as to how to OC. When you put some of the things in this thread into practice, we'll have loads more to go on, in the event of any issues.

Have a little re-read of the posts given you so far, refresh your brain with the info. That's what I do. My theory is if you throw large volumes of sh1t (info) at a wall (my brain) then some of it will eventually "stick". Do a couple of days of tests and then post back with some templates of what you tried, perhaps a screenshot or two and any results, both good and bad, such as "When I did this, a bad thing happened" and "After I did this, Prime ran for twice as long" etc.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

You must be seeing it, it's a certainty. I can understand however that if not 100% familiar with things you can miss it.

TO see MCH Ref scale up as you change VTT (CPU Termination) do the following:

Set VTT to 1.20V
Set MCH ref to your new desired value, so for now type 0.740V
Use the arrow keys to go back up to the CPU termination setting.
While pressing page up and page down (to increase and decrease CPU termination) watch the numerical value of MCH ref.

You will then clearly see that as you increase CPU termination, MCH Ref will also go up. As you then decrease CPU Termaination, you will see it go back down.

You seem to be an alert kind of chap and have shown willing to learn which is good. You now must get stuck in and get some settings tried. As BoombasticSloth says, you eed to experience how things you change effect your PC. Be a little more confident. You're now armed with all the knowledge you need. It's time to make a concentrated effort to put it all together. I know you have only a small amount of time to dedicate to this, so it's best to make your time spent count.

At this stage, there's not really any more info anyone can give as to how to OC. When you put some of the things in this thread into practice, we'll have loads more to go on, in the event of any issues.

Have a little re-read of the posts given you so far, refresh your brain with the info. That's what I do. My theory is if you throw large volumes of sh1t (info) at a wall (my brain) then some of it will eventually "stick". Do a couple of days of tests and then post back with some templates of what you tried, perhaps a screenshot or two and any results, both good and bad, such as "When I did this, a bad thing happened" and "After I did this, Prime ran for twice as long" etc.

Thanks for getting back to me. Your assistance has been helpful. I tend to get caught up in the details but it's also what "I do". If that makes sense. I'm very detail oriented and notice things that most people don't. I tend to do things in a very efficient manner so I'm sure this has caused this to drag out longer than need be. Meaning I look to ask a question, get an answer, if no answer then "bump" and sometimes by then it's forgotten what point I was at and then I start over thinking it's quicker than doing a search and sifting through tons of info. I find clarification, when working with these sort of things, helpful. Often buzz words are used and since this isn't my area (at least yet, ha) it can be easy to get lost. So, thanks again for your help.

I did go into the BIOS and set the CPU Term (1.2v) and the MCH Ref (.74). I then moved back up to CPU Term and changed it and could see that the MCH Ref changed. Example: 1.24 CPU Term = .765 MCH Ref. So I should have checked to see if the opposite is true (I would assume but I'll check based on my opinion of assumptions when working with such things). Meaning will adjusting the MCH Ref change the CPU Term. I'm going to not use the terminology VTT for my sake as it only adds a bit of confusion at this point.

So I'm going to try CPU Term at 1.2v and MCH Ref at .74v and test with Prime95 and see what happens. If it fails then I understand that I should drop the MCH down a notch and try for stability again. So the point being is we're trying to OC with the voltage as low as possible. The longer between failures in Prime95 then I'm heading in the right direction. But it seems I may need to increase MCH Ref to become stable. And then the idea to be able to run it over night (8 - 12 hours I guess) with no errors and you know your good. Then, tweak a bit more to get a higher Ghz speed out of the CPU which may mean pushing up the MCH Ref or CPU Term. That sound right? Based on earlier notes of yours it sounds like it's okay to use ET6 or is that only for testing GFlops for the VCore?

Edit: Vdroop - The vcore is set to 1.28125v in the BIOS but CPU-Z says 1.264v this is while CPU is idle.

[BoombasticSloth]

Re: Stable E8400 OC - stock voltages

So I should have checked to see if the opposite is true (I would assume but I'll check based on my opinion of assumptions when working with such things). Meaning will adjusting the MCH Ref change the CPU Term.

Edit: Vdroop - The vcore is set to 1.28125v in the BIOS but CPU-Z says 1.264v this is while CPU is idle.

The opposite will not hold true. Changing the Mch ref will not change the vtt, but I gather you figure that out by now if you have tried it.

Vdrop = difference between what you set in the BIOS and what you see in CPU-Z at idle.

VDroop = difference between idle reading and 100% CPU load reading.

From post #234.

[SBMongoos]

Re: Stable E8400 OC - stock voltages

Then:

Vdrop - The vcore is set to 1.28125v in the BIOS but CPU-Z says 1.264v

Vdroop - The vcore is set to 1.28125v in the BIOS but CPU-Z says 1.248v

ET6 had been showing correct "target" info until recently. Now when I check the CPU Term and MCH Ref with ET6 the MCH Ref does not match the BIOS. ET6 shows lower.

Is it not recommended to adjust the MCH Ref after changing the CPU Term? It seems if you adjust the CPU Term and the MCH Ref changes automatically that there is a reason for it so I'm wondering if it's best to go with this. I've tried adjusting the MCH Ref seperately but so far all is failing.

[Chike]

Re: Stable E8400 OC - stock voltages

ET6 had been showing correct "target" info until recently. Now when I check the CPU Term and MCH Ref with ET6 the MCH Ref does not match the BIOS. ET6 shows lower.

The "stupid" ET6 show reference values as they are for default vtt, it may be good or bad, depend on your point of view.

[Psycho101]

Re: Stable E8400 OC - stock voltages

As chike said, ET6 reports refs in a different way. I've gotten used to it as have others but it can be confusing, so best not to worry about it. ET6 will always show MCH and CPU Ref to be what ever figure it becomes at 1.2CPU Term. So if you have 0.760V MCH Ref at 1.2CPU Term then even if you set CPU term to 1.4V, ET6 will still show 0.760V. If you have MCH Ref set to 0.720V @ 1.2V CPU Term, then ET6 will always show 0.72V etc, etc.

The idea of changing MCH Ref when CPU Ref is 1.2V is so that you get the correct % scaling.

Your plan for testing seems good and I look forward to seeing what you find out. Remember though that with a dual core it's usually the case that less MCH Ref is better.

For tuning CPU Term and MCH Ref, set a Vcore you know is enough for the speed you want and do the following:

CPU term to 1.2V, MCH Ref at default 0.760V
Increase CPU term to 1.22, 1.24, 1.26, 1.28, 1.3, 1.32, 1.34, 1.36, 1.38, 1.40, testing after each change to CPU Term. Don't touch MCH ref after initially setting 0.760 @1.2 CPU Term

CPU Term to 1.2V and MCH Ref to 0.740V
Increase CPU term to 1.22, 1.24, 1.26, 1.28, 1.3, 1.32, 1.34, 1.36, 1.38, 1.40, testing after each change to CPU Term. Don't touch MCH ref after initially setting 0.740 @1.2 CPU Term

CPU Term to 1.2V and MCH Ref to 0.720V
Increase CPU term to 1.22, 1.24, 1.26, 1.28, 1.3, 1.32, 1.34, 1.36, 1.38, 1.40, testing after each change to CPU Term. Don't touch MCH ref after initially setting 0.720 @1.2 CPU Term

CPU Term to 1.2V and MCH Ref to 0.700V
Increase CPU term to 1.22, 1.24, 1.26, 1.28, 1.3, 1.32, 1.34, 1.36, 1.38, 1.40, testing after each change to CPU Term. Don't touch MCH ref after initially setting 0.700 @1.2 CPU Term

Lower than 0.700MCH Ref at 1.2V CPU Term isn't often needed, and you should find the best value between 0.760 and 0.70V for a dual core.