[SOLVED] CPU speed slows down once unplugged and running only on battery.

[Dalleuh]

CPU speed slows down once unplugged and running only on battery.

Found this out once I replaced a once dead battery for years, the new one charges fine and laptop has no issue expect the obvious CPU speed drastically dropping.

Also an SSD has been installed on the laptop, that s the only thing that logically I can think of and could be impacting the battery power delivery, thus making the CPU run on lower speed in order to privde power to the SSD? just my theory.

Plugged on AC can reach 2,5GHz

Unplugged and on battery only drops to less than 0,8GHz

Any input on this to help fix this is appreciated.

Many thanks!

 

[Rokinamerica]

Have you gone into the control panel and made sure the power options are set to performance and not power saving plan?

 

[Dalleuh]

Have you gone into the control panel and made sure the power options are set to performance and not power saving plan?

yes definitely, both plugged and unplugged are running on the same power plan which is the recommended one.
Also changing the minimum CPU utilisation to 100% doesn't fix the issue, as this is a speed issue.
Thanks!

 

[Roland Of Gilead]

Hey there,

So, we are a little short on info here. Can you please give us the make and model of your laptop. Otherwise, we are just guessing.

 

[Roland Of Gilead]

Something to try. Download and run Throttlestop.

Once the app is open, click on the limits button and the TS Bench button. Then run the default bench. In the limits box, there will be some lights that may turn yellow or red. They will highlight whether the reason for your slow clockspeed. It could be 'EDP Other', etc. This will tell us if your CPU is throttling. Which I suspect.

When was the last time the laptop was cleaned? Have you ever replaced the thermal paste? Are you using any other program to control the CPU?

 

[Dalleuh]

Hey there,

So, we are a little short on info here. Can you please give us the make and model of your laptop. Otherwise, we are just guessing.

the laptop is ASUS X555L, but the CPU model is showing on the screenshots it is i5-5200.

Something to try. Download and run Throttlestop.

Once the app is open, click on the limits button and the TS Bench button. Then run the default bench. In the limits box, there will be some lights that may turn yellow or red. They will highlight whether the reason for your slow clockspeed. It could be 'EDP Other', etc. This will tell us if your CPU is throttling. Which I suspect.

will do that

When was the last time the laptop was cleaned? Have you ever replaced the thermal paste? Are you using any other program to control the CPU?

laptop was cleaned very recently, nothing else controlling the CPU

 

[USAFRet]

A laptop running on battery often/usually throttles the system down.

 

[Dalleuh]

Something to try. Download and run Throttlestop.

Once the app is open, click on the limits button and the TS Bench button. Then run the default bench. In the limits box, there will be some lights that may turn yellow or red. They will highlight whether the reason for your slow clockspeed. It could be 'EDP Other', etc. This will tell us if your CPU is throttling. Which I suspect.

I tried that but I honestly don't know what is going on, here is a screenshot after the TS Bench ended:

 

[Roland Of Gilead]

I tried that but I honestly don't know what is going on, here is a screenshot after the TS Bench ended:

This is showing you your CPU is hitting it's max temp, and is thermal throttling. This is what BD Prochot (essentially processor hot)

You may need to repaste thermal paste on CPU. You will have take the heatsink off the CPU clean the old paste and repaste with something like Noctua NT-H1.

 

[Dalleuh]

Could you please elaborate more?
With changing the battery, I also changed the fan. Previously the old fan was making ticking noise, so I open the laptop's lid and block the fan deliberately, and I know for a fact that the CPU's cores temp can reach 100C (using core temp) but this is while plugged in.

I did the same test while plugged in now

the temp is near 90C.

enough of me rambling, so if I understood correctly, the laptop while unplugged and on battery has a setting that if it reaches a certain temp (50/60 from the first test) then the CPU will be thermal throttling? I suppose there is a way to stop this while on battery or change the value to have a higher temp (similar or less than when plugged in?

much appreciated!

 

[Dalleuh]

Issue Fixued by clearing the BD PROCHOT box on the main screen of ThrottleStop

 

[Roland Of Gilead]

Issue Fixued by clearing the BD PROCHOT box on the main screen of ThrottleStop

Good. Glad you got it sorted.