(SOLVED) TurboBoost/EIST vs OC = confusion (i5-760)

[wpcoe]

I decided to experiment with overclocking my i5-760 tonight and came away with questions.

Is it inevitable that EIST and other power saving features are ignored once you overclock? Every BCLK that I used, the multiplier was 22 (not 21...) and it stayed there permanently. I expected the multiplier to drop when the CPU was idle. When *not* overclocking, the multiplier drops to 9 (for speed of 1.2Ghz) when the system is idle or under low load.

Is it inevitable that TurboBoost is ignored once you overclock? I've read online guides that say to make sure you disable it before overclocking, lest it kick in and send your multiplier too high.

I would like to run my system modestly overclocked to 3.3GHz (BCLK 150 x 22), but have the multiplier drop when under light load or idle. I'd also like to have TurboBoost kick in when appropriate. Is that possible?

Another concern I have with this mobo (P55A-UD3P) is the slim choice for RAM multiplier (6, 8 or 10). With a BCLK of 150, that mean I have to clock my RAM at either 900, 1200 or 1500Mhz. I was in urgent need to rebuild my system so I bought low-end Kingston 1333 Value RAM. Should I underclock at 1200, or do you think it's safe to clock that RAM at 1500? I found I can undervolt the RAM (even running at 1500Mhz) at 1.4V.

Any idea why my i5-760 is running with a 22x multiplier (as reported by CPU-ID anyway) rather than 21x? Even when not overclocking CPU-ID reports 22x (2.93Ghz).

I was able to OC to 4.04Ghz and pass the "High" level of Intel BurnTest. ("High" is the highest level I can use with only 4GB of RAM.) My preferred modest OC at 3.3Ghz is stable using 1.075v Vcore and 1.4V on RAM.

 

[betasub]

Depends entirely on BIOS.

For my ASUS P7P55, by default any overclocking causes pretty much all power saving settings in BIOS to revert to off/disabled, but they can all be reset again manually to my preferred settings to enable full power saving and Turbo states while maintaining my overclock.

As for the 22x multiplier, it seems the +1 multiplier state normally associated with Turbo has been enabled on various boards (ASUS and Gigabyte included) without the normal requirement you'd expect.

 

[futuristicmonkey]

Depends entirely on BIOS.

For my ASUS P7P55, by default any overclocking causes pretty much all power saving settings in BIOS to revert to off/disabled, but they can all be reset again manually to my preferred settings to enable full power saving and Turbo states while maintaining my overclock.

As for the 22x multiplier, it seems the +1 multiplier state normally associated with Turbo has been enabled on various boards (ASUS and Gigabyte included) without the normal requirement you'd expect.

I've noticed that 22x multiplier as well on my Asus P7P55D-Deluxe.

What annoys me is I have Q-fan disabled for my chassis fan(it comes with a potentiometer to control its speed anyway) and when EPU is in auto, when it goes into idle mode (9x multi) the fan will slow down. When going back into high-performance/turbo mode the fan won't speed up again unless I go into Fan X-pert and manually set Q-Fan to disabled again.

 

[ehume]

With my Gigabyte boards I can enable EIST, C1E, C-states. But the system becomes unstable and crashes. I can enable Turbo Boost at elevated BCLK's; but if the peak cpu clock is too high, the system crashes.

 

[wpcoe]

I have not disabled EIST, TurboBoost, C3/C6, etc ... they all still show enabled. That's why I used the word "ignored" in my opening post.

When I use stock (auto) settings with no overclock, I can see EIST and TurboBoost working on a regular basis. Once I overclock, they don't work -- even though those features are not disabled in BIOS.

 

[NumericalMethods]

I use EIST and speedstep on my setup to get variations in multiplier and voltage. Trick is you must use offset voltage control ie. +0.0125V settings to allow the EIST to work. As soon as you use absolute ie. 1.325V then EIST is disabled. I also don't use LLC, not sure if that effects the EIST voltage variations.

 

[EarthwormJim]

Have you tried updating your BIOS? My Asus p55 board was a little odd with overclocking and power saving settings at first, till I updated the BIOS. EIST was not working at high bclk settings just like with you till that update.

Power saving features don't work quite right if you use a forced voltage vs an offset voltage too.

I do know most boards disable full turbo mode once you go above a certain bclk, or if you select a one higher multiplier than normal multiplier.

 

[wpcoe]

I went to the Gigabyte web site to see what the latest BIOS version is (it's F11, the one I have), and the description states: "Improve Intel Turbo Boost compatibility".

Hmmm. If they were mucking with TurboBoost in that revision, maybe I should try reverting to F10. Too late in the evening now, but maybe in the morning....?

I'm also intrigued by using "offset voltage control," as I'm not familiar with it.

 

[ehume]

If you find offset voltage control on your Gigabyte board, pm me quick.

 

[wpcoe]

If you find offset voltage control on your Gigabyte board, pm me quick.

Good news/bad news: I *think* I found the equivalent of "offset voltage control," but it's "greyed out" and not adjustable.

In BIOS, just below CPU Vcore there's an item called Dynamic Vcore (DVID) .

I tried changing a multitude of other settings from "auto" to see if it would unlock the DVID setting, but to no avail.

Only by changing the CPU Vcore to "Normal" is Dynamic Vcore (DVID) enabled. If you select CPU Vcore to be "Auto," or specify a value, then Dynamic Vcore (DVID) is disabled, with a value of +0.00v.

 

[wpcoe]

I decided to see what the Gigabyte "EasyTune" utility did. It basically has three pre-set overclocks to choose from (2.94, 3.15 and 3.8 GHz). I tried each one:

The 2.94GHz (option 1 in EasyTune) permits EIST and TurboBoost to operate, but 3.15 and 3.8 GHz (options 2 and 3) do not.

I also discovered that when manually tweaking in BIOS (i.e. not using EasyTune) that I can specify a multiplier from 9x to 22x. Interesting, since the i5-760 is advertised as a 2.8Ghz chip = 21x133.

When I manually specify a 22x multiplier everything reports the same (after booting) as when I choose 21x.

I suspect there is a higher point above 3.06 Ghz where EIST/TurboBoost still work, but will save that experimenting for another day. (Unless I get bored enough today. :biggrin I got bored ... see following post.

BTW, the EasyTune software is flaky at best. Clicking on the shortcut triggers the UAC prompt, the cursor goes to the busy-in-the-background mode, but nothing happens 9 times out of ten. When it *does* work, all it does is put an icon in the system tray that you have to right-click and choose "show". Yuck.

Also, I'm not comfortable overclocking my cheap 1333 Kingston ValueRam much above 1400.

 

[wpcoe]

[NB: This post has been heavily edited...]

Criminy, I can be so dense.

I thought having C1, C3/C6, EIST, etc on "Auto" was *enabling* them to *auto*matically do what they need to do. No, indeed. The choices for the settings are: "Auto, Enabled, Disabled."

Soooo, I *enable*d them, and lo and behold SpeedStep works even when overclocked. I'm reluctant to enable TurboBoost at this speed (3.65Ghz).

I'm currently o/c'd using 22x 166MHz in BIOS with a RAM multiplier of 8 (to keep it at 13333), and all voltages set at "Auto".

At idle it SpeedSteps down to 9x (1.5Ghz), and shows 1.312v.

At load it powers up to 22x (3.65Ghz), and shows 1.328v.

While I like CPUID's CPU-Z, is there another reliable monitor utility that shows the speed of each core?

 

[Termie]

[NB: This post has been heavily edited...]

Criminy, I can be so dense.

I thought having C1, C3/C6, EIST, etc on "Auto" was *enabling* them to *auto*matically do what they need to do. No, indeed. The choices for the settings are: "Auto, Enabled, Disabled."

Soooo, I *enable*d them, and lo and behold SpeedStep works even when overclocked. I'm reluctant to enable TurboBoost at this speed (3.65Ghz).

I'm currently o/c'd using 22x 166MHz in BIOS with a RAM multiplier of 8 (to keep it at 13333), and all voltages set at "Auto".

At idle it SpeedSteps down to 9x (1.5Ghz), and shows 1.312v.

At load it powers up to 22x (3.65Ghz), and shows 1.328v.

While I like CPUID's CPU-Z, is there another reliable monitor utility that shows the speed of each core?

I've been following this thread as I'd like to do the same kind of overclocking you're trying to do (i.e. with power savings). But your idle voltages say that you're not getting a true voltage reduction, even though the processor is stepping down to a 9x multiplier. My i7-860 idles at 0.87v. I've had the same problem (failure to go into power savings when overclocking past a certain point), which is frustrating. Also, since you're using automatic voltage control, you're getting a pretty high voltage at load (1.328), probably creating more heat than you need at 3.65 (just a hunch - don't know the appropriate voltage for that speed).

 

[NumericalMethods]

At the x9 multi my i5 idles at 1.085V. At full load it will increase to 1.367V and then droop to 1.320V. Sounds like at the moment, when you load the CPU your board is raising the voltage to counter vdroop.

You need to disable LLC or vdroop to get this sort of behaviour. I don't run LLC as you can't tell what the maximum voltage your CPU is ever exposed to (you can have a guess). If you disable it you will need to re-establish your CPU voltage (it will have to be set higher).

The details of why LLC behaves the way it does and why I'm not a fan are in this article:

http://www.anandtech.com/show/2404/1

 

[betasub]

wpcoe: glad you've managed to enable power saving states, but as Termie points out,you should be seeing lower voltages also.

Similar to you, I have 9x167 for 1.5GHz at idle, but ASUS PC Probe shows my voltage dropping to 1.02V, and then to 0.89-0.90V, as CPU activity approaches minimum.

Loading 3-4 cores on my i5-750 gives 21x167 for 3.6GHz, and forcing the load onto 1-2 cores lets Turbo kick the multiplier to 23x and then 24x for 4.0GHz. Auto-voltage does seem a little excessive at 1.325V under load, but temps only really concern my when I'm burn-testing all 4 cores.

If you are interested in viewing each cores multiplier dynamically, try Tmonitor from the folks at CPUID.

 

[wpcoe]

I think Gigabyte's use of the word "Auto" in BIOS settings is my nemesis.

I made a simple change from "Auto" to "Normal" for Vcore and look at the difference:

The voltage/temps for "Full load" were taken during Intel BurnTest at High Stress Level.

BTW, I did not tamper with Dynamic Vcore (it's still at +0.000v) nor with LLC (set to auto).

 

[NumericalMethods]

Normal setting is the voltage requested by the chip - the VID of the chip if you like. For the i series chips this varies with the speedstep multiplier. Normal is what you should use for normal operation. Auto setting is what Gigabyte thinks your chip might need to run a 3.6GHz. This will typically be a conservative estimate and therefore really quite high, since you are overclocked. You may find that 'Normal' is not enough voltage for your given chip at overclocked speeds. After all, this is the voltage that Intel sets for the chip to run at stock settings. To improve stability you may want to start offsetting the normal voltage. ie all voltages that the chip requests get +0.05V added to them, for example. Forget auto, use Normal settings and test for stability. Add offset voltage as required determined by your testing. Job done

 

[EarthwormJim]

I also discovered that when manually tweaking in BIOS (i.e. not using EasyTune) that I can specify a multiplier from 9x to 22x. Interesting, since the i5-760 is advertised as a 2.8Ghz chip = 21x133.

When I manually specify a 22x multiplier everything reports the same (after booting) as when I choose 21x.

That's completely normal. The 22x multiplier setting is taking advantage of turbo boost. Turbo boost has a 1 higher multiplier setting for when 4 cores are partially loaded. Since that setting applies to all 4 cores, motherboard manufacturers are able to treat it like it's a normal multiplier option. True turbo boost gets disabled though.

 

[wpcoe]

To improve stability you may want to start offsetting the normal voltage. ie all voltages that the chip requests get +0.05V added to them, for example. Forget auto, use Normal settings and test for stability. Add offset voltage as required determined by your testing. Job done

So, that's what the "Dynamic Vcore (DVID)" setting would be for, right? It's now making sense that it would only be accessible when setting the CPU Vcore to "Normal."

The only potential instability I've seen is a couple times Windows Explorer froze ("stopped responding"), but I'm not sure I can blame that on overclocking/undervolting.

That's completely normal. The 22x multiplier setting is taking advantage of turbo boost. Turbo boost has a 1 higher multiplier setting for when 4 cores are partially loaded. Since that setting applies to all 4 cores, motherboard manufacturers are able to treat it like it's a normal multiplier option. True turbo boost gets disabled though.

Interesting. Why not just do away with that TurboBoost option? With my i5-760 at stock settings (21x 133MHz), I *never* have seen it running at 21x in CPU-Z. It basically just seemed to flip from 22x to 9x, never using the 21x level.

Why even bother with 21x? Wouldn't Intel prefer to advertise the i5-760 as a 2.9 Ghz CPU than a 2.8 Ghz CPU?

 

[EarthwormJim]

So, that's what the "Dynamic Vcore (DVID)" setting would be for, right? It's now making sense that it would only be accessible when setting the CPU Vcore to "Normal."

The only potential instability I've seen is a couple times Windows Explorer froze ("stopped responding"), but I'm not sure I can blame that on overclocking/undervolting.



Interesting. Why not just do away with that TurboBoost option? With my i5-760 at stock settings (21x 133MHz), I *never* have seen it running at 21x in CPU-Z. It basically just seemed to flip from 22x to 9x, never using the 21x level.

Why even bother with 21x? Wouldn't Intel prefer to advertise the i5-760 as a 2.9 Ghz CPU than a 2.8 Ghz CPU?

At certain loads (4 threads at 100% utilization) the CPU would probably exceed the TDP of the processor at a 22x multiplier

Remember, turboboost's multiplier settings are dictated by the current power consumption of the processor, and always remains below the TDP.

 

[wpcoe]

Thanks. This all starting to sink in and make *some* sense to me now.

I decided to test some altered "Dynamic Vcore (DVID)" settings:

The previous two tests ("Auto" and "Normal" above), the Dynamic Vcore was set at "Auto". (Yeah, I know...) Should I be happy with the lower Vcore voltages now being reported when the CPU is at low load? Or, is there a point were low is too low, and if so, am I close to that level?

And, I think I've been misled on the CPU multiplier being reported by CPU-Z. Or, CoreTemp is doing drugs. CoreTemp shows much more frequent changes in the multiplier, and much wider assortment of multiplier ratios.

CPU-Z simply shows 9x or 22x. CoreTemp is all over the place including such multipiers as 16.5, 16.0, 12.5, 10.5, 10, and 9.5! So, while it is correct that I never saw 21x displayed with CPU-Z, maybe if I stared at CoreTemp, I would see it once in a while?

 

[wpcoe]

While I took the time to post the above message, of course my CPU was mostly at 9x with .88v, and the fans had a while to cool things down.

Current core temps reported by both CoreTemp and HardwareMonitor are 27-30°! I do have the aircon runnning, but my room temp is 25° C.

 

[CrArC]

Ah, what an excellent thread! I see you've discovered Gigabyte's interesting interpretation on how voltages and system settings should behave.

I can confirm your observations on a GA-P55A-UD4 and i5-760:

- System always reports Turbo multiplier (22x) on POST
- Voltages set to Auto or Normal may overvolt when overclocking
- Power saving settings on Auto may disable themselves on overclocking
- If you get it all running, you can enjoy a reasonable overclock with chilly 30-degree idle temps and Turbo enabled

i5 760 multiplier range:
9x-21x standard
22x all-core Turbo
25x max Turbo

CPU-Z and other applications aren't great at handling the way the Core CPUs shuttle through frequencies. Use [url="http://www.cpuid.com/softwares/tmonitor.html]TMonitor[/url] from the CPUID chaps to see core frequencies in real-time and greater accuracy! Great for making sure Turbo runs as well.

With all power saving settings and Turbo manually enabled, Turbo may still choose not to run (or to run as fast) when overclocked. This looks to be a joint decision based on voltages and power consumption, temperature and other parameters.

In fact for me, this was most likely to happen if I enabled Gigabyte's Dynamic Energy Saver feature while overclocked. DES would work with Turbo happily, but on reboot Turbo would be disabled until DES was turned off and the system rebooted again.


For anyone's reference, my settings in the BIOS:

Core i5-760 150MHz BCLK/ QPI x32 = 1350MHz idle / 3150MHz norm / 3750MHz max Turbo
OCZ Reaper OCZ3RPR1600C6LV4GK @ 1500MHz 6-8-6-21-1T (undervolted to 1.58v)

CPU Advanced settings: All set to Enabled

Advanced Memory Settings: Performance Enhance set to Standard, mem multi x10

QPI/VTT: 1.15v explicitly defined (not Auto/normal)
Vcore: 1.1675v explicitly defined (not Auto/normal)
VDDQ (RAM): 1.58V explicitly defined (not Auto/normal)
PCH Core: explicitly defined as it's stock voltage (can't remember what that is, but again not Auto/normal)
PLL: 1.8v explicitly defined (not Auto/normal)
CPU Clock Drive: 800mV
PCIE Clock Drive: 900mV


I see idle temps of 29-32 degrees, load around 49-52 degrees! Really enjoying the 1156 platform!

 

[NumericalMethods]

PCH Core default is 1.05V and should stay there until trying to push past 4GHz really.

CrArc, you have set your BIOS very similarly to how I set my Asus BIOS. I just disabled the C-states to leave 20 * 190 BCLK = 3.8GHz as my maximum CPU frequency. Explicitly defining all the major voltages is the way to go.

 

[wpcoe]

Thanks for those specific values. :thumbsup:

I just started getting a POST beep: one long beep. Only thing I found via Google was old messages (6-7 years ago) saying one long beep on Award BIOS was RAM-related. That's next on my list to check on.