Saving energy while overclocking; dropping CPU multiplier at idle.

My 875k on a MSI P55 GD55 seems to be running fine, can get it stable at 4ghz (133x30).

However, when monitoring the CPU at stock speeds I can see that at idle, it drops to about 1200mhz with a multiplier of 9.

The problem is, once I overclock it (changing mulitiplier but keeping everything else the same; including C state on) it always seems to stay between 3800-4000mhz (28-30 multiplier) no matter what task I'm performing.

Perhaps its a functionality that is missing in my mobo, but I would like to the multiplier to be able to drop all the way to it's min. of 9 like it does when running at stock speeds instead of staying at 28-30 all the time.

Any suggestions on this matter?

EIST and C1E are designed to help with that so make sure they are on if your overclock is stable. They should be dropping you CPU multiplier and frequency when idle. Also, looking for your boards manufacture website will help if you they have power saving software. And updating the bios usually helps with these sort of problems

Have a look here & see if your boards bios has something similar.

I have a gigabye 1366 lga...the bios is completely different. Good video to explain what your can do with you chip. Not many applications use 4 cores so Hyper-threading 2 cores may be in your best interest with less heat. 3 core with HT will give a major boost as its proven 3 cores are better than 4 when running several apps, but will give way to extra heat.

Thanks for the help.

After reading your post, I set EIST and C1E from "Auto" to Enabled to ensure they were on. However, my multiplier when OCed still stays 28-30.

I also made sure my BIOS had the latest version.

Additionally, I made sure that all settings from stock (where it downclocks to 1.2 ghz) were identical to the my OCed settings minus of course, the multiplier.

I watched the video as well... its very very close to what I want. But basically, it seems like his mobo automatically drops his OCed processor to 1.2ghz even when its OCed. (Unless I missed something?) Mine for some reason, does not. In fact, it seems like everyone else's mobos still drops the speed to 1.2ghz even when OCed... mine being the exception. I wonder if anyone else has experienced this problem?

Is speedstep/spread spectrum on? Most mobos have that on always so that should be dropping you cpu speed/heat on idle. Also try changing the C-State to C3 and see if that helps. Setting it to Auto can help too just to test...
What are your memory settings at? Download CPU-Z 1.54 to find out...they can cause instability if tweaked.

Man just so you know, i went to EVGA's site to get some info on how their boards are working with the Core i7 875k. It seems you are not the only one having this problem. The only thing i dont know is if its a chip issue or a motherboard issue in the bios...

Here is the link so you can see...LINK

Killador said:

Man just so you know, i went to EVGA's site to get some info on how their boards are working with the Core i7 875k. It seems you are not the only one having this problem. The only thing i dont know is if its a chip issue or a motherboard issue in the bios...

Here is the link so you can see...LINK

Click to expand...

Hey man, thanks for the link.

I literally tried everything you said right before I read your post, it was actually weird because I set C-state to C3 and then read your post right after that bootup.

Just been toying with all the settings, turbo on/off/auto, tweaking memory, setting memory to auto, leaving it to stock, etc etc etc. Nothing works. The CPU only downclocks 1 or 2 multiples when it's OCed.

It appears from your link that mobo manufacturers are aware of it but won't do anything or don't know how to fix it yet as the 875k is pretty new.

But at least EVGA has support, in my past experience, MSI has nonexistent support so I expect to be waiting for awhile on a resolution to this issue.

Ah well... gonna toy with some more settings but in the meantime I guess I'm just gonna leave it stock except load an OC profile for gaming sessions etc.

Actually, I just read MIAHALLEN's OC guide from a different thread in this forum

http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/

and he reccomends that the C-State and Speedstep and other power saving features be turned off when OCing.

I wonder if my mobo is doing that automatically and overriding my manual settings when the multiplier is changed. That is, they automatically disable power saving features when they detect an OC.

However, from the video linked earlier in this thread it seems obvious that at least SOME people are able to get Speedstep working in conjunction with an OC...

My setup in sig does 1800mhz at idle at less than 1.1v and 4000mhz at load with 1.25 and 1.2 vtt
all perfectly 100% rock solid stable no matter what I throw at it since march.

The trick is having a cpu that will do it and a mobo that will cater to it settings wise.

Qusus said:

Actually, I just read MIAHALLEN's OC guide from a different thread in this forum

http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/

and he reccomends that the C-State and Speedstep and other power saving features be turned off when OCing.

I wonder if my mobo is doing that automatically and overriding my manual settings when the multiplier is changed. That is, they automatically disable power saving features when they detect an OC.

However, from the video linked earlier in this thread it seems obvious that at least SOME people are able to get Speedstep working in conjunction with an OC...

Click to expand...

Turning off power saving features - You do this if you are trying to achieve a certain level in your overclocking adventure. For instance, if you are trying to get to 4.0GHz - turning those features off will help reduce OC failure. Turning them off stablizes the CPU frequency the higher you go. Only after you have found your perfect speed from the bios then you can turn them on. This is a re-assurance that your OC is working very well and is balanced. Of course running Prime 95 and other programs like it help verify if your current set up is good enough for the tempratures you get while the computer is working.

Some people (even myself) have ran a PC without powersaving features before. Then i looked at my electric bill...so i had a change of heart and turned them on. There is no OC i run without power saving now

Anyway, here is what i suggest you do and its a pain, but we kinda wana find out whats happenening or try to. Press F11 in the bios and Save your overclocked profile so you dont lose it. If you need to releod your previous profile you can hit F12. Reset everything (usually F7) to default and restart your PC. Look at CPU-Z 1.54 (if you downloaded already) and see if the clocks go down. If yes, go back to the bios and overclock your CPU to 3.0GHz first using 20x multiplier only. Increase the base clock and it should calculate for you what frequency your chip is running at and in this case we just want 3.0GHz first. Restart and check to see if the CPU reacts the same. If yes, clock it to 3.8GHz with the baseclock only and 20X multiplier. You should be able to get this clock with only 1.23vcore. Restart and check for the clocks going down and the multiplier again. If yes, then clock 20X200 set up should work perfectly with 1.32vcore (may need more vcore im not 100% sure). Test with turbo disabled as well so you may restart this a couple of times.

If this works, check your motherboard software disk for APS (Active Phase Switching) software and turn it on if everything goes well, or just to check if it helps your OC.

If this doesnt work I will try to suggest something else because your board has more features than most P55 or X58 boards today.

Your detailed instructions are much appreciated. Don't worry about my BIOS settings, as I have 6 profiles saved for testing.

Here's my results using CPU-Z 1.55.

Loading the default settings of the mobo, at stock speeds (133x22) of 2.93ghz, idle clocks go down to 1.2ghz.

Upping multiplier to 133x24, with all settings identical, keeps the CPU idling at 3.2ghz at all times. No down clock.

Upping multiplier to 133x24, this time with TURBO disabled, still keeps CPU idling at 3.2ghz. No down clock.

Going to mess with the base frequency right now and will report back results:


OK interesting... I up the base frequency and keep the multiplier stock,

At a 150mhz base frequency, the CPU still downclocks to about 1.4ghz when idle (multiplier drops to 9 at idle).

At 175mhz base frequency, I get the same effect at idle (multiplier drops to 9 at idle).

Same with 200mhz base frequency.

Also, I do the same experiment except this time, I manually DOWNCLOCK the multiplier to 20 and up the base frequency. Like before, the CPU still downclocks properly at idle speeds.

According to the back of my mobo box, this motherboard does indeed come with Active Phase Switching. I imagine it is already integrated into the mobo as there is no utility for this in the included software disc.

Here's the ultimate conclusion:

If I don't up the multiplier past the stock rate of 22, my power saving features work fine, even if I up the base frequency.

If I move past the stock multiplier of 22, the CPU never downclocks when idle.

Deductive reasoning points to this being a bug with the board on MSI's end. Since these were the first 1156 CPU's with an unlocked multiplier, I imagine MSI overlooked this feature in their board. Can't think of anything else as I've literally tried almost all permutations of settings.

The difference between the wattage draw on idle w/o power saving and without is not a significant difference on your electric bill. Do the math guys before people start thinking this will save more than $5 /month on a PC thats on in an idle state 24/7. Kill, the way you make it sound its like they will save $50 or something! You would be better served powering it off when you arent using it to save more quid.

50W (Amount of Power saved on idle) /hr x 24 (hours in a day) = 1200W (per day) saved. 1.2kw x .07kwh (cost of power) = .084 savings /day * 30 days = $2.52 If you double the cost of electricity or the wattage saved, thats $5 /month if it was idle 24/7 for 30 days.

Please tell me I got that math right...


The guide suggests to disable to ensure you have a stable overclock without those items getting in the way. Hit your clockspeed goal without it enabled first, then turn it on and see if it works (which it should).

EarthDog said:

The difference between the wattage draw on idle w/o power saving and without is not a significant difference on your electric bill. Do the math guys before people start thinking this will save more than $5 /month on a PC thats on in an idle state 24/7. Kill, the way you make it sound its like they will save $50 or something! You would be better served powering it off when you arent using it to save more quid.

50W (Power savings on idle) /hr x 24 = 1200W per day saved. 1.2kw x .07kwh =1.2*.07 = .084 savings /day * 30 days = $2.52 If you double the cost of electricity or the wattage saved, thats $5 /month if it was idle 24/7 for 30 days.

Please tell me I got that math right...


The guide suggests to disable to ensure you have a stable overclock without those items getting in the way. Hit your clockspeed goal without it enabled first, then turn it on and see if it works (which it should).

Click to expand...

Totally agree. I only run one desktop and the true energy saving benefits come from turning it off when I'm not using it. (Your math looks right, however, I think the savings would be a little higher for people living in say... NYC, than someone living in MI like me.)

That being said, I would still like to figure out a way for my CPU to idle properly when the multiplier is changed.

Ah, I understand the purpose of disbabling power saving, turbo etc now. I've been hitting my clockspeed goals with those enabled anyways so I can see it doesn't apply to me.

EarthDog said:

The difference between the wattage draw on idle w/o power saving and without is not a significant difference on your electric bill. Do the math guys before people start thinking this will save more than $5 /month on a PC thats on in an idle state 24/7. Kill, the way you make it sound its like they will save $50 or something! You would be better served powering it off when you arent using it to save more quid.

50W (Amount of Power saved on idle) /hr x 24 (hours in a day) = 1200W (per day) saved. 1.2kw x .07kwh (cost of power) = .084 savings /day * 30 days = $2.52 If you double the cost of electricity or the wattage saved, thats $5 /month if it was idle 24/7 for 30 days.

Please tell me I got that math right...


The guide suggests to disable to ensure you have a stable overclock without those items getting in the way. Hit your clockspeed goal without it enabled first, then turn it on and see if it works (which it should).

Click to expand...

I thought the smiley face would help lighten the mood... but i guess not.

Qusus said:

Your detailed instructions are much appreciated. Don't worry about my BIOS settings, as I have 6 profiles saved for testing.



Here's the ultimate conclusion:

If I don't up the multiplier past the stock rate of 22, my power saving features work fine, even if I up the base frequency.

If I move past the stock multiplier of 22, the CPU never downclocks when idle.

Deductive reasoning points to this being a bug with the board on MSI's end. Since these were the first 1156 CPU's with an unlocked multiplier, I imagine MSI overlooked this feature in their board. Can't think of anything else as I've literally tried almost all permutations of settings.

Click to expand...

This is why increasing the base clock is sometimes better than using the multiplier. Problem solved!!

Killador said:

I thought the smiley face would help lighten the mood... but i guess not.

Click to expand...

Killador said:

This is why increasing the base clock is sometimes better than using the multiplier. Problem solved!!

Click to expand...

Only problem with that is raising the bclk vs just raising the multi uses more watts... LOL. Damned all the way around it seems.

EarthDog said:

Only problem with that is raising the bclk vs just raising the multi uses more watts... LOL. Damned all the way around it seems.

Click to expand...

At idle with a 9x multi, i run at 2.2ish i think, which is only 400mhz below this chips stock speed, so that means that at idle, it's still chewing through power.

I'd love to have an unlocked chip. That way everything can actually run independently, and i won't have to have crazy fast RAM to get a decent OC :/ (Min RAM multiplier, and max CPU, and my RAM is still OCed by 60MHZ)

CompuTamer said:

At idle with a 9x multi, i run at 2.2ish i think, which is only 400mhz below this chips stock speed, so that means that at idle, it's still chewing through power.

I'd love to have an unlocked chip. That way everything can actually run independently, and i won't have to have crazy fast RAM to get a decent OC :/ (Min RAM multiplier, and max CPU, and my RAM is still OCed by 60MHZ)

Click to expand...

That's was the reasoning why I got this unlocked chip... ah well.

In the meantime, I think I'm going to take Killador's advice and just run at a stock multiplier with a slightly higher base frequency until I can figure out some other solution to this. Even with a higher base frequency, it's still better than running at 4.0ghz all the time.

Haha, it's kind of true I'm damned all around (but less so with one way)... basically the real solution would be if MSI fixed this on their end imo.

Thanks for all the help and comments guys.

Another thing i just remembered and over-looked is the Power Options in windows Control Panel. Make sure they are at 'Balanced'. You can change your sleep state to whatever you want. This helps a lot too