CPU Speed Locked

ArazelEternal · 04 Aug 2015

Hello all,

I have had something really odd going on for a while now that I have never seen or heard of before. This started back when I was running Windows 8.1, so it isnt new to the Windows 10 installation. Every now and then my laptop will get really slow. When I look at the task manager, I will see that CPU usage never goes above 47% and it seems like it is speed locked to 1.19 Ghz.

Dell Latitude E4310
Core i5 540M @ 2.53 Ghz, Turbo to 3.06 Ghz
8GB RAM
180 GB Intel 330 Series SSD
Windows 10 Professional

Those are the specs. This happens even right after a clean install with absolutely nothing else on it except for what comes with Windows. Ive looked into the BIOS to make sure those settings are valid and Ive looked into the power options under windows to make sure something isnt weird there. I have no idea what is causing this. Has anyone here ever seen something like this?

Snakeyes · 04 Aug 2015

Could it be the CPU throttling due to excess heat? Shouldn't happen with a clean install but a clogged fan , high ambient temperatures, or other hardware cooling issues could cause the overheating.

ArazelEternal · 04 Aug 2015

No. IM pretty anal about keeping this thing clean, as I am with my desktop as well. According to HWMonitor the CPU is running below 60C and sometimes even down to 45C. Not even close to overheatting so it isnt a heat issue.

Snakeyes · 04 Aug 2015

At the risk of being redundant, have you checked C states and speed step? Also tried setting Minimum processes state 100% in power management.

ArazelEternal · 04 Aug 2015

I dont see anything about C states in my BIOS. I went through every setting. Is there a way I can look at that in Windows? Speed Step is activated in the BIOS, and I tried setting the power profile to high-performance which sets the minimum processor state to 100% and that didnt seem to change anything.

Mystere · 04 Aug 2015

You do realize that by default Windows combines your two cores into a single graph. If you have one CPU core running at 100% and the other idle, it will show 50% cpu usage.

This sounds like you have a task that is in a heavy cpu loop using a single core.

ArazelEternal · 04 Aug 2015

Yes, Ive looked into that. I have it set so it shows each logical processor as a seperate graph. In this case it shows four as this Core i5 is a hyperthreaded dual-core. During an instance of this issue, it will show each core at just below 50% usage so it isnt just using one core.

Advent · 12 Aug 2015

Hi, I saw this on a mate's laptop a few weeks ago. I found a cure but he said he has to redo it every so often.
Shut down your laptop,remove the power cord and the battery.Plug the power cord back in and start your laptop just on mains power.
Let it run for a few minutes then shut down,remove power cord and put your battery back in.
Plug power cord back in and reboot then check your cpu status in task manager.

Hope this helps.

ArazelEternal · 11 Feb 2016

Hey, sorry its been so long since I came back to this.

I found out what was causing the issue.

Apparantly Dell adapters have an issue where the wire for the center pin in the power plug comes unsoldered. This pin is so the laptop can communicate with the adapter and determine the wattage. It could no longer do this so it would default to low power settings and throttle the CPU to keep power usage down. Buying a new adapter fixed this.

kevinchio · 24 Apr 2016

Hi
I read your post here, which was solved by replacing a new adapter.

I have a similar problem on my Samsung Laptop. I did also buy a new adapter but it works only occasionally. Most of the time it was locked at 47%, sometime it went back to full after restarts.

Did your new adapter completely solve your problem? Do you think if there is any problem on the laptop side may cause the problem?