3570K Overclock, have no clues.

[BrksEverything]

Greetings AnandTech, y'all have been a huge source of info for this lurker as I planned and put together my new build. However, I'm in the process of OC'ing my 3570K, and am running into some issues that I wasn't able to trouble-shoot by reading others' similar questions. My specific issues and build are below, and any/all help is most appreciated. Thanks.

Build:
3570(k), cooled by Arctic Freezer i30 (air)
Asus P8Z77-V Pro
G.Skill Ripjaws X DDR3 1600 (2 x 8gb)
Corsair HX 650w

I've been able to reach a stable 4.6 overclock, with CPU-Z reporting 1.232 V, by setting the multiplier, and setting the VCore manually to 1.215 in the BIOS.

1. My first question is why the discrepancy between what I set the voltage to in the BIOS, and what it's actually running at? This discrepancy also exists in the BIOS, as there is a cpu voltage read-out right next to the manual/offset setting, and it is likewise different than the figure I type in the box.

2. Secondly, for every-day usage, I would like to have the CPU throttle back down in speed and voltage. I understand there is a way to do this using offset voltage instead of manual, but I've had a hard time getting it to work:

a. Using manual voltage, while stress testing, CPU-Z reports 1.232 Core, and Coretemp reports VID to be 1.1809. Subtracting 1.181 from 1.232 gives + 0.051 (this is my offset right?).

b. Going back into BIOS, and changing manual mode to offset, a couple of things happen - first, the cpu voltage reported by the bios is still different than what I typed in to manual mode, and sometimes different than what CPU-Z was when i did my VID calculation. Nevertheless, I change the mode to offset, enter the .050 (rounding), and try to reboot, but this results in windows hanging at startup.

With the exception of having set my DRAM speed to the factory specs, most other settings in BIOS are on AUTO.

Please let me know what I may be doing wrong, and thanks.

 

[BrksEverything]

Okay, so I just tried the above described offset process again, this time I disabled C3 and C6 first, and it still resulted in windows failing to load, followed by a BSOD.

Upon rebooting back into BIOS, the CPU core voltage read-out to the left of the off-set/manual setting showed 1.060, which is a significant drop, and probably has something to do with why this isn't working....

Just wanted to toss that in there as well.

 

[BrksEverything]

Alright, last post for a while, just had to further complicate things:

Following a simple offset tutorial from another website, I reset optimized settings in BIOS, then went for a 4.4 overlcock using +.050 offset voltage.

Now I'm more confused than ever: In CPU-Z, under no load, I'm still running at 4400MHz constantly, though I thought the whole point of offset was to allow the CPU to throttle down when not under load. Further, my Vcore is at 1.216 while idle, but then DROPS to 1.161 under load?

I guess I really don't understand how this works, and am going to set everything back to stock before I break something. Hence my name.

 

[Face2Face]

I will try to answer some of these questions, I am still learning myself.

1. I believe your voltage is reporting higher on CPU-Z because of the LLC setting (maybe to high?) Have you adjusted that setting yet? I have read if the LLC is too high then you be using more voltage then what is set in your bios. I am not familiar with Asus boards, but there maybe an LLC options from 1-10

2. I am using an offest voltage on my overclock. I use it along with turbo. You will need to find out what your base voltage is and adjust it from there. I don't have LLC adjustments on my board, so I have a fair amount of vdroop. My base voltage in the bios is 1.064 and I added + 0.235 to my offset and set my turbo to 48 on all cores and I am very stable. I have seen my CPU-Z voltages at 1.308 to 1.282 100% load- quite a bit of vdroop, but I play games and stress tested for hours and hours and It's stable.

3. Not sure about coretemp voltages. I don't use them as reference.

I am going to attempting a manual overclock soon and disable offset and turbo. Trying to get a better understanding on how much voltage I really need to be 100% stable.

EDIT - I also wanted to ask with your 4.6 overclock, if you have c3/c6 enabled does your core speed and voltages decrease at idle?

If anyone else wants to chime in and correct me or help, I'm sure he would appreciate it.

 

[dave_the_nerd]

I was under the impression, from observing my 3570K that the voltage was pretty much a Cartman/Maury "Whatever! I do what I want!" kind of thing on the part of the CPU?

I OC'd to a measly 4.2 since I have a stock cooler. I didn't touch my voltage setting though, and I've seen it vary anywhere between 1.03v and 1.2v while running under load. (While I'm using the machine to surf the web, F@H running and CPU-Z open.)

 

[Face2Face]

I was under the impression, from observing my 3570K that the voltage was pretty much a Cartman/Maury "Whatever! I do what I want!" kind of thing on the part of the CPU?

I OC'd to a measly 4.2 since I have a stock cooler. I didn't touch my voltage setting though, and I've seen it vary anywhere between 1.03v and 1.2v while running under load. (While I'm using the machine to surf the web, F@H running and CPU-Z open.)

Yes, if your voltage is set to AUTO in your bios, then the voltage will vary.

 

[BrksEverything]

@Face2Face, thank you for the insight, the C3/C6 disabling was done on a lark, but I quickly re-enabled them, as they were in use for my 4.6 stable OC, and I believe they are important for energy efficiency. Basically, if I don't understand what it does, I'm realizing I shouldn't mess with it.

@Dave, that was an awesome comparison, and made me crack the hell up.

I think I've been able to determine the difference in the voltages I was telling the BIOS to use, and the voltages it was actually using were a result of Load Line Calibration, which I have a very tenuous understanding of. There is an option in my BIOS to mess with it, but it seems to be pretty important, and not something negative at all, especially since I'm going for performance + longevity.

With regard to not throttling down at idle, I've been able to determine from a similar post on here that it was due to my Windows performance setting dictating the minimum CPU usage to be 100%, and I've since knocked it down to about 5%, which allows throttle down, but even with task manager showing 0% CPU load, the frequency bounces back and forth from 1600MHz to 3400MHz, seems kinda frantic, but maybe that's just the nature of the beast?

In any event, it's painfully clear there is much more going on here than meets the eye, and I'm still trying to sort it all out. Thanks very much for the help so far!

 

[Vectronic]

Nature of the beast... <1% usage the CPU will (should) be idling at 1600MHz, then between 1% and about 25% it will scale up to full clock.

Task Manager (or anything else really) only measures once per second, however your CPU can go from idle, to 100% and back again hundreds of times in that second. Hence, bouncy clock speeds.

LLC can be a pain, but once you have it figured out, you shouldn't have to worry about it again, you'll either use 100% for fixed voltage, or whatever level you found worked for offset.

C3/6/States and SpreadSpectrum *should* be disabled, it makes stability significantly easier to achieve... C1E is optional, doesn't make as much of a difference. If your PC "seems" stable after a quick stress test, and has been fine for an hour... but then BSODs when you aren't really doing anything... minimize a window, maximize a window... go to the bathroom... that's probably C1E/3/6/States.

 

[dave_the_nerd]

Yes, if your voltage is set to AUTO in your bios, then the voltage will vary.

Is it necessary to set it higher manually to achieve more aggressive overclocks like OPs?

 

[BrksEverything]

Is it necessary to set it higher manually to achieve more aggressive overclocks like OPs?

Yes, my original overclock was done by manually finding and setting a voltage (in theory the lowest possible stable voltage), and while I was pretty satisfied with the results, I am now trying to figure out a better long-term solution through offset that I hope will allow me not to have to run at that frequency and voltage when not needed.

I have heard that you can overclock by offset out of the gate, but the general consensus I've seen is that by determining a known stable voltage for a given frequency manual (constant) overclock first, then calculating the offset, it is much easier. My experience hasn't quite matched that yet.

If you are just upping the multiplier without setting the voltage, then I believe you will quickly "hit your head" on a voltage ceiling (probably dangerous for your cpu), or a heat ceiling (not good, but not as dangerous). I could be wrong, so others feel free to correct me.

 

[Face2Face]

Is it necessary to set it higher manually to achieve more aggressive overclocks like OPs?

Usually on most 3570K's you can get to 4.2Ghz stable just changing your Turbo to 42 on all cores and keeping your voltage on Auto. On most chips, anything higher you will need to add voltage either to your base or offset.

 

[Face2Face]

With regard to not throttling down at idle, I've been able to determine from a similar post on here that it was due to my Windows performance setting dictating the minimum CPU usage to be 100%, and I've since knocked it down to about 5%, which allows throttle down, but even with task manager showing 0% CPU load, the frequency bounces back and forth from 1600MHz to 3400MHz, seems kinda frantic, but maybe that's just the nature of the beast?

Are you seeing you voltage drop when you PC is at idle?

Like Vectronic says, when you are finding your best voltage for an overclock it's best to disable to remove one more point of a BSOD. Then when you find you stable clock and voltage I would enable it and see if you are still stable.

 

[Vectronic]

Upping the multiplier is fine on any setting but having your VCore on "auto". If it's on fixed or offset, you can increase the multiplier all you want, the worst that will happen is a BSOD.

Not that this will be all that helpful for you, but this is the relationship between fixed and offset for me:

The most noticeable thing is how much more voltage offset requires to be stable than fixed.

Edit: @ Face2Face, C3/6/States doesn't affect voltage or clocks, EIST/SpeedStep/Turbo is what effects that. The C-States are how the processor behaves at certain states... ie: what is going through it, or what parts are active. A brief description.

 

[Face2Face]

Hey Vectronic - Are you currently running a Fixed OR Offset overclock? EDIT - Is you chart showing voltages with C3/C6 enabled?

 

[BrksEverything]

Vectronic, thank you very much for the info - if you don't mind my asking, which type of OC do you use, and why?

My biggest frustration right now is figuring out how to convert my results in manual voltage mode to offset, since there seem to be more variables in play.

 

[Face2Face]

The most noticeable thing is how much more voltage offset requires to be stable than fixed.

Edit: @ Face2Face, C3/6/States doesn't affect voltage or clocks, EIST/SpeedStep/Turbo is what effects that. The C-States are how the processor behaves at certain states... ie: what is going through it, or what parts are active. A brief description.

Gotcha... So if you running a fixed voltage can you enable EIST and speedstep as well to bring down the volts and clocks at idle?

 

[Vectronic]

The chart is all with C3/6/States disabled, C1E was still enabled, but has since been disabled as well because it makes > 4.5GHz easier to get stable.

I'm running Offset (-0.005) @ 4.5GHz, which ends up being about 1.256v at load, LLC is at "3" (or 50%)... at LLC 1 (100%) I can use -0.030v.

"Why" do I use offset?... because I don't see the point in running at the full 4.5GHz (or whatever other clock) all the time, but more importantly I use offset because it reduces the voltage at idle speeds which increases the life-span of the CPU, and also reduces temperatures.

It's trial and error really, that's why I made my own charts... going by VID values when using Fixed and trying to equate that to Offset wouldn't work very well for me if I tried it either, it's off by about 0.025v usually.

Your best bet is to use Fixed voltage with 100% LLC that will get you the closest to VID - Fixed = Offset.

But really, you just gotta play with it, keep testing, keep dropping or increasing the voltage, etc.

Edit: Nope, SpeedStep/Turbo will have no effect with fixed voltages at dropping voltage, depending on the board it will still drop clocks though, but your still pumping 1.3v through the CPU at 1600MHz... a little bit pointless as far as I'm concerned.

 

[BrksEverything]

Thanks for the insight, that chart is amazing

Is there any drawback to leaving LLC at high levels (75-100), or should I try to get it back down once I've found a stable offset?

Similarly for C3/C6?

 

[BrksEverything]

I ask because right now I'm zero-ing in on offset stability for 4.6Ghz, 1.006 v idle, 1.248 v load, with C3/C6 off, CE1 AUTO, LLC at 'ultra high' (75%), and wondering if once I've found stability then I'm good to go, or if I really need to try to revert those settings back to default for CPU health and longevity.

 

[Vectronic]

The behavior of LLC depends on the board, some boards will over-compensate at higher levels of LLC and will apply a higher voltage than what is set or necessary for a given clock.

LLC is designed to compensate for vDroop, the voltage drop when a load is applied to the CPU (going from 1.200v at idle to say 1.150v at 100% load). You can generally get your CPU stable at any setting/level of LLC, what you are trying do to is find the best level for LLC... the one that keeps your voltage closest to what it was set to in the BIOS, and the one that keeps vDroop to as small amount as possible.

I use either LLC1 (100%) or LLC3 (50%) because LLC2 (75%) on my board makes the voltage waiver/jump around too much, and anything below LLC3 (25%, 0%) doesn't compensate enough, and will crash at the beginning of an applied load.

C3/6 pretty much only come into play at Sleep/Hibernate... if you use those, then your CPU will use *slightly* less voltage when it's not doing anything, might be handy for laptops, for desktops not really significant at all.

C1E can be a bit trickier, and disabling it can cause odd things to happen like your PC not "waking up" properly from Sleep, with a decent board/components shouldn't be an issue, but keep it enabled as long as you can... at 4.6GHz you should be able to keep it enabled.

LLC will only cause degradation if it is over-volting, if it's behaving normally/properly shouldn't affect longevity at all.

Any of the C-States has pretty much zero effect on longevity unless your PC spends 90% of it's time in sleep mode... in which case it might last 35 years, instead of 34 years.

 

[BrksEverything]

Thank you very much for the info, this has been an enormous help!

One last question,

LLC is designed to compensate for vDroop, the voltage drop when a load is applied to the CPU (going from 1.200v at idle to say 1.150v at 100% load). You can generally get your CPU stable at any setting/level of LLC, what you are trying do to is find the best level for LLC... the one that keeps your voltage closest to what it was set to in the BIOS, and the one that keeps vDroop to as small amount as possible.

It's my understanding from an old article linked to above (circa 2007), that vdroop is a good thing, and while minimizing it makes it easier to overclock, allowing it to serve it's purpose protects the CPU from voltage dips and spikes. Does LLC negate this safety feature, or does it no longer work this way? Also, I've noticed that my idle voltages are lower than my load voltages, does this mean I've circumvented how this whole thing is supposed to work?

 

[Idontcare]

It's my understanding from an old article linked to above (circa 2007), that vdroop is a good thing, and while minimizing it makes it easier to overclock, allowing it to serve it's purpose protects the CPU from voltage dips and spikes. Does LLC negate this safety feature, or does it no longer work this way? Also, I've noticed that my idle voltages are lower than my load voltages, does this mean I've circumvented how this whole thing is supposed to work?

You need to put things into perspective.

On a scale of 1-10 for "bad" with 10 being the worst, if LLC is to be labeled "bad, don't do it" and given a score of say 5 then overclocking on its own would be labeled "bad, don't do it" and given a score of 8.

When you decided to throw caution to the wind back whenever the risks of OC'ing were assessed and evaluated by yourself, and you determined "the risks are outweighed by rewards" you were in essence saying "I am ok with doing anything to my chip provided it is no more harmful than an 8 out of 10 on the 'badness' scale".

That was when you crossed the bridge, perhaps without realizing it at the time, and any concerns you may have regarding the perceived dangers of LLC are now overshadowed by the more pressing concerns you are supposed to be having (or be OK with ignoring) from OC'ing your processor in the first place.

Kinda like routinely driving drunk but wondering if you should lose a few pounds because the doctor says your weight is borderline unhealthy. You got bigger lifestyle issues to be concerned about before being concerned over shedding 5 lbs becomes a priority

 

[BrksEverything]

You need to put things into perspective.

On a scale of 1-10 for "bad" with 10 being the worst, if LLC is to be labeled "bad, don't do it" and given a score of say 5 then overclocking on its own would be labeled "bad, don't do it" and given a score of 8.

Thank you for the perspective, that's certainly something I lack in this department. I realize OC'ing is by its very nature, strictly speaking, making something do what it was not intended to. But even within this 'field' of enthusiasm, there are generally accepted norms of what is considered relatively safe(ish), or not, and where in this continuum LLC fit in is exactly what I was wondering, so thanks!

I'm aware of, and comfortable with, the possibility of killing my machine, but I won't be too worried until I start tapping on my CPU with a hammer.

Seriously though, your threads are epic.

 

[UaVaj]

unless here is a major reduction of cpu life span. just put it at max safe vcore and call it a day.

willing to say most will upgrade before cpu ever dies.

 

[BrksEverything]

unless here is a major reduction of cpu life span. just put it at max safe vcore and call it a day.

willing to say most will upgrade before cpu ever dies.

Well, I'm a big believer in 'rules of thumb'. I don't have the time to devote to fully understanding everything that goes on under the hood of my rig, nor do I expect the members of this forum to educate me on all the finer points of the electrical engineering that may be in effect on my machine.

I'm just following on-line guides like a lot of other people and trying to get a good-enough grasp of the situation to try what I'd like to, with the understanding that I may screw up in any myriad number of ways, and that's on me, but if possible still avoiding the major pitfalls that can and should be avoided. For instance, anyone who intends to delid long-term without knowing about the pump-out effect of your standard paste-TIMs is going to have a bad time, and the only reason I know that is because of 'idontcare' and others on these boards.

Minimizing risk, if you will, with the understanding that by doing what I'm doing already I'm at a much greater risk than those who don't overlcock. And I'm okay with that.