• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

i7 920 CPU locked at 100% usage!?

lettuce

lettuce

lettuce

Associate
Joined
15 Oct 2007
Posts
2,186
Location
Bedfordshire, UK.
I have had this problem for a good few month now and have started a thread before but with no real solution....

http://forums.overclockers.co.uk/showthread.php?t=18452661&highlight=usage+username_lettuce

Basically i started to notice that my CPU was reporting a 100% usage in programs like RealTemp, CPU-Z, EasyTune 6 etc even though i wasnt stressing the CPU at all other than browsing the net, i have all the correct CPU settings enabled in the BIOS (c3/c6/c7,C1, EIST etc)

I have worked out how to remedy the issue but only for short periods!. Basically if i go into Control Panel>Hardware and Sound>Power Option and if i select 'Resort default settings for this plan' for the active power plan then the CPU Usage stops being 100% used and goes back to normal levels, it even works even if i havent changed any settings in the power plan from default!.

I dont have a clue what would cause the CPU usage to be lock at 100% and by resorting default settings would help cure the problem for a while even if i havent changed any of the settings for the active power plan from default??
 
What does task manager say ?
If your CPU usage is 100% then you have a program running eating up all the spare CPU cycles.
Could be a DC client or bitcoin miner.
Or even worse, a real nasty that is encrypting your files.

These programs will stop if they detect activity from the keyboard or mouse.
Bring up task manager and watch it for a few minutes without any keyboard or mouse input.


I am assuming your actually seeing 100% CPU usage and not associating running at full clock speed with 100% usage.
 
Something in there does seem to be interfering. I think your best bet is to clear CMOS and do a clean install at stock settings. Take an HDD image of your OS partition and then start reinstalling all that you want and see if (and if so isolate the casue) it re-occurs or not. Then when resolved re-apply the oc.
A pain, but the best way to proceed im my view.
 
PCZ said:
What does task manager say ?
If your CPU usage is 100% then you have a program running eating up all the spare CPU cycles.
Could be a DC client or bitcoin miner.
Or even worse, a real nasty that is encrypting your files.

These programs will stop if they detect activity from the keyboard or mouse.
Bring up task manager and watch it for a few minutes without any keyboard or mouse input.


I am assuming your actually seeing 100% CPU usage and not associating running at full clock speed with 100% usage.
Click to expand...

It reports 99% for System Idle Process, and nothing else is taking up any CPU usage really. It only reports about 5% CPU usage when RealTemp is saying its 100% usage, im inclined to believe RealTemp over task manager, as my CPU core temps raise in temperature when RealTemp is reporting 100% cpu usage so this backs that stat up

eddyr said:
Something in there does seem to be interfering. I think your best bet is to clear CMOS and do a clean install at stock settings. Take an HDD image of your OS partition and then start reinstalling all that you want and see if (and if so isolate the casue) it re-occurs or not. Then when resolved re-apply the oc.
A pain, but the best way to proceed im my view.
Click to expand...

I tried a compete system format and fresh install a while back and slowly install programs but could never pinpoint a problematic program. I even tried install the bare minimal programs and after a day or so the problem started happening again

This still doesnt answer why if i Resort default settings for the power plan in use the cpu starts operating normally??
 
Last edited:
lettuce said:
It reports 99% for System Idle Process, and nothing else is taking up any CPU usage really. It only reports about 5% CPU usage when RealTemp is saying its 100% usage, im inclined to believe RealTemp over task manager, as my CPU core temps raise in temperature when RealTemp is reporting 100% cpu usage so this backs that stat up



I tried a compete system format and fresh install a while back and slowly install programs but could never pinpoint a problematic program. I even tried install the bare minimal programs and after a day or so the problem started happening again

This still doesnt answer why if i Resort default settings for the power plan in use the cpu starts operating normally??
Click to expand...

Did you remove the oc/restore default settings alongside the reformat and it still persisted? What progrmas did you have installed and were you on latest board drivers?

On the software side could perhaps be something iffy stored on any data drives you have.

What do other monitoring programs report?
 
The load meter in RealTemp reports the percentage of time the CPU is in the C0 state. By default, most CPUs will be in the C0 state when they are working on something and when there is nothing to do, they will drop down to the low power C1 state. This saves power and allows the CPU cores to run much cooler when idle. When Task Manager reports a low number while RealTemp is reporting 100%, that means your CPU is being prevented from using the C1 low power state. This is usually a Windows power profile issue.

Performance wise, there is nothing wrong with having your CPU in the C0 state 100% of the time. That just means that it is always ready to immediately get to work on anything you throw at it. There actually is some tiny performance advantage to doing this but unless you are benching and trying to set a world record, it's not worth the extra power consumption and heat. That's why C1 was invented.

The latest version of RealTemp shows the percentage of time your CPU cores and CPU Package are spending in the low power C States like C3 and C6. Most other monitoring software will ignore what your CPU is really doing.

RealTemp T|I Edition
http://www.overclock.net/t/1330144/realtemp-t-i-edition
 
i could be dpc/interrupts caused by bad drivers or failing hardware, the normal task manager just seems to class these as idle usage even though they can kill a computers performance. If you run process explorer then it will give a bit more info on whether its dpc/interrupts, although it wont help identify the cause. You could also try the DPC latency checker
 
Go to advanced settings in your power plan, then CPU utilization and change minimum processor usage from 100% to 10%. Click apply. The problem shouldn't occur after this when idling.
 
alex_123_fra said:
Go to advanced settings in your power plan, then CPU utilization and change minimum processor usage from 100% to 10%. Click apply. The problem shouldn't occur after this when idling.
Click to expand...

Its 5% on default aways, not 100%.

Ok to answer the other questions, i have the latest BIOS version, i have try previous version and had the same issue

Avast! & Malwarebytes report no suspect programs

Yeah i tried a fresh install on stock clocks

At the moment it is behaving itself and RealTemp T|I is reporting 0.0 across all states

I am beginning to wonder if its a hardware conflict. I have a StarTech PCI capture card in the system and have noticed that when i load the capture program for the card (AmaRec) that even though im not capturing any footage (i just have the program open) the CPU usage jumps to 100% according to RealTemp and then stays there even after the program is closed, the increase in system temps also back this up. Now usually i would agree that having the CPU at 100% usage constantly wouldn't be too much of a concern, but when im capturing and the CPU is at 100% usage when it shouldn't be the temps sky rocket and are at 75-80c so this does become a concern!
 
Last edited:
Looks like you have found the offending hardware/software. Don't know a thing about capture cards, are they alternate programs that you can use?
 
Yeah there are other programs, but still give the same issues. I have asked another member on another forum who has the same capture card, and he states that his never put his to 100% CPU usage when using the device/program
 
lettuce said:
...i have all the correct CPU settings enabled in the BIOS (c3/c6/c7,C1, EIST etc)
Click to expand...

The RealTemp C States window shows that C3, C6 and C7 are all disabled. This is common on the first generation Core i boards. As soon as you start overclocking and increase the BCLK speed, the bios automatically turns off all of the low power C States. It completely ignores your choices if you enabled any of these in the bios.

When you run your capture card software and RealTemp shows 100.0%, does the Task Manager continue to show a very low number? I think that is what is happening. This means the driver for your capture card is a piece of crap. It is disabling the low power C1 state in your CPU. I assume that it is doing this to prevent dropouts when capturing video. Some developers that were not very good at writing driver software for multi core hyper threaded CPUs used a few tricks to keep the CPU in the C0 state 100% of the time to cover up their poor programming.

If they never released any updated software then I guess you will have to find a better capture card with an updated driver or use your Power Options trick to re-enable the C1 low power state every time after you use this card.

Keep in mind that if the Task Manager is not showing your CPU fully loaded then it is not fully loaded. It is just stuck in the C0 state, doing nothing, when it should be idle in the C1 state. That's what RealTemp is telling you.
 
The capture software is most likely deliberately preventing the CPU from entering the C1 state in an attempt to reduce latency.

This will mean your CPU cant drop to idle clocks and core voltage, making it run a bit hotter than it otherwise would.

Your initial post was a bit misleading though as you don't actually have 100% CPU usage at all.
On the face of it you have nothing of any significance loading up the CPU, it is just being prevented from entering the C1 state.
 
unclewebb said:
The RealTemp C States window shows that C3, C6 and C7 are all disabled. This is common on the first generation Core i boards. As soon as you start overclocking and increase the BCLK speed, the bios automatically turns off all of the low power C States. It completely ignores your choices if you enabled any of these in the bios.

When you run your capture card software and RealTemp shows 100.0%, does the Task Manager continue to show a very low number? I think that is what is happening. This means the driver for your capture card is a piece of crap. It is disabling the low power C1 state in your CPU.
Click to expand...

Well as said i have asked a member on another forum who has the same capture card as me and he says he doesnt have any problems at all with the CPU being at 100% usage all the time when using the capture program. So maybe its a case of having an old i7 CPU, maybe if i had a more up to date i7/i5 chip then i the C states would work correctly? I will build a new Haswell system come June/July time, so we'll see if i get the same issue on that system
 
Has the person on the other forum used RealTemp to diagnose the problem? If he is only going by Task Manager then he may be missing out on what is really going on with the CPU.

Your CPU is fine. It's just poorly written software that is causing the problem.

Keep in mind that it is not the CPU being at 100% load all the time. It is the CPU being locked into the C0 state and being prevented from using the low power C1 state that is the problem. This and a 100% load on the CPU are 2 different things.
 
You must log in or register to reply here.
Back
Top Bottom