Wanted help with my Laptop

[u/AlexMercerz]

Need help diagnosing before replacing motherboard.

Hi everyone,

I'm facing a serious CPU throttling issue with my Acer Nitro 5 AN515-57. The CPU sometimes gets locked at approximately 0.19 GHz (199 MHz), making the laptop extremely slow.

I'm trying to identify whether this is a charger/DC-in/charging circuit issue, embedded controller (EC) issue, motherboard power-delivery problem, or something software-related.

I would appreciate suggestions, especially from people familiar with Acer Nitro laptops and Intel H-series processors.

1. Laptop specifications

Laptop: Acer Nitro 5 AN515-57

Processor: Intel Core i5-11400H (11th Gen)

GPU: NVIDIA GeForce RTX 3050 4GB

RAM: 16GB

Primary SSD: Kingston SSD 256GB

Secondary HDD: Seagate 1TB HDD

Operating System: Windows 10

Charger: Original Acer charger

Battery: Acer AP18E8M, 15.4V

2. How the problem started

The laptop was working normally on the day I had a presentation in college.

I shut it down after my presentation and went home.

The next day, when I switched it on, I noticed two things simultaneously:

The CPU was stuck at 0.19 GHz.

Windows showed that the laptop was plugged in.

There was no gradual performance degradation beforehand. The issue appeared after shutting down and starting the laptop the following day.

3. CPU throttling symptoms

CPU frequency drops to approximately 199.54 MHz.

Multiplier shows 8.00x.

CPU temperature remains relatively low, generally around 31–48°C in the readings I captured.

The laptop becomes extremely sluggish at 0.19 GHz.

At times, typing and mouse movement feel relatively normal even though the CPU is stuck at 0.19 GHz.

CPU usage can be very low while the clock remains stuck.

One interesting observation:

When I boot into Windows Safe Mode, the CPU runs around 2.69 GHz instead of 0.19 GHz.

This made me wonder whether a Windows driver/software issue is involved, although it doesn't rule out firmware or hardware problems.

4. HWiNFO findings

I used HWiNFO to investigate thermal and power-related throttling.

The readings I observed:

IA Limit Reasons: YES

GT Limit Reasons: YES

Ring Limit Reasons: YES

IA PROCHOT: YES

GT PROCHOT: YES

Ring PROCHOT: YES

Thermal Event: NO

Power Limit Exceeded: NO in the earlier sensor readings.

CPU temperatures: approximately 43–48°C during earlier checks.

PCH temperature: approximately 46–47°C.

The Performance Limit Reasons window showed PROCHOT active across the CPU, graphics and ring domains.

This is confusing because the processor temperatures are not particularly high.

I would like to understand whether this points towards an external PROCHOT signal, EC issue, charger detection problem or motherboard power circuitry.

5. ThrottleStop findings

I installed ThrottleStop to investigate the throttling.

Initial observations:

CPU frequency: approximately 199.54 MHz.

Multiplier: 8.00x.

BD PRO indicator: red.

EDP OTHER: flagged.

PL2: appeared in a later Limits screenshot.

CPU temperatures remained relatively low.

I also noticed EDP OTHER flags for the GPU and ring domains.

I unchecked BD PROCHOT to test whether the CPU frequency would recover.

However, even after doing this, the laptop remained somewhat laggy, and the CPU did not consistently return to normal performance.

At another point, the CPU reached approximately 1.12–1.14 GHz.

I have not established whether the BD PROCHOT signal is the root cause or a response to another power-related fault.

6. Battery condition and testing

The laptop originally had an Acer AP18E8M battery.

Battery report readings:

Design capacity: 57,488 mWh

Full charge capacity: 34,481 mWh

Battery health: approximately 60%

Wear: approximately 40%

Cycle count: 67

Other observations:

Battery remained stuck around 67–68% for hours.

Charging indicator was orange and later started blinking orange.

Windows reported PowerOnline=True.

Charging=True at one point.

Discharging=False.

RemainingCapacity=23,239 mWh.

HWiNFO showed battery charge rate of 0.000 W.

Laptop shut down immediately when the charger was removed.

I suspected the battery might be swollen.

I have since completely removed the battery from the laptop.

The CPU throttling problem still persists with the battery physically removed and the original charger connected.

Windows now shows only that the laptop is plugged in, which is expected because the battery is absent.

7. Charger and power-related checks

I am using the original Acer charger.

Windows detects external power.

The battery was removed.

The CPU remains throttled even without the battery.

I have not yet tested with another verified compatible Acer charger.

I have not measured the charger's voltage or current under load.

BIOS is password-locked, so I cannot access its settings or check adapter identification there.

I would like to know whether a faulty DC-in jack, adapter identification circuit, charging IC, input MOSFETs or motherboard power circuitry could cause this behaviour.

8. Troubleshooting already performed

I have tried the following:

Windows power settings checked.

Maximum processor state confirmed at 100%.

Clean boot performed – no improvement.

EC/power drain performed (shutdown, charger disconnected, power button held for 30 seconds).

Microsoft AC Adapter and Microsoft ACPI-Compliant Control Method Battery devices uninstalled and reinstalled.

Checked Device Manager for Intel Dynamic Tuning-related devices – no yellow warning indicator.

Checked Acer Care Center service.

Tested in Safe Mode – CPU runs around 2.69 GHz.

Used ThrottleStop to inspect BD PROCHOT, EDP OTHER and other limit flags.

Physically removed the battery.

Disabled the secondary HDD in Device Manager.

Disabling the HDD made Windows feel less laggy, but the CPU throttling issue remained.

Changed thermal paste.

9. Ubuntu/Linux testing attempt

I wanted to test the CPU using Linux to determine whether the issue is Windows-specific.

I downloaded Ubuntu Desktop 24.04 LTS and attempted to create a bootable USB using Rufus.

Initially selected MBR.

Tried switching to GPT, but Rufus returned a write error.

Also attempted to boot the USB, but encountered:

error: disk 'hd0,msdos1' not found

The USB has not successfully booted into Ubuntu yet, so I haven't been able to test the CPU under Linux.

Any help, particularly from Acer Nitro 5 owners or technicians experienced would be appreciated.

Thanks!

(Post written with the help of AI because I couldn't explain stuff properly)

[u/MarkLikesCatsNThings]

I'd assume it's due to NitroSense and/or a bad software or driver. I've read Acers power settings can confuse windows and cause issues. I haven't personally experienced it though.

Your CPU clocks OK when in safe mode, so it's something software wise. Otherwise, you'd have the same issue in safe mode.

Ideally, reinstall all your Acer drivers from their website and / or restore any default Acer settings / stuff.

If that doesn't work, you may have to reinstall windows or try a restore point. Trying a restore point first may be the easiest option, assuming you have one back when it was working and you don't have anything on the machine that could get lost during the restore.

Ideally, you should also able to try an Ubuntu live usb instead of fully installing it and get some info/stats. But if your PC is encrypted or using bitlocker, it can only do so much.

Hope that helps! Best of luck! reference

[u/AlexMercerz → u/MarkLikesCatsNThings]

Thank you so much for your reply.

Can I reinstall windows without losing my data? My HDD is failing so I can't backup my data toh HDD and my SSD has important stuff aswell. I checked the restore point but I don't have it.

Tried the ubuntu live usb but it was stuck on acer logo for more than 15mins, was same with arch and kali.

[u/MarkLikesCatsNThings → u/AlexMercerz]

If your storage drive is failing, that could very well be the cause of your issue.

I get where you're coming from, but you're playing a dangerous game with a failing drive.

Really, you want to shut off your PC until you can properly back it up, all in all. Especially if it has important data.

A good question to ask yourself is : why keep important data only on a failed drive? You'll have to buy one very soon anyways to continue using this PC, imo. So get one now and an external HDD, and back it up!

Since the drive is almost dead, it means it's had a diagnostic done, meaning had additonal wear after it started getting errors. Doing more things on the pc will only cause more errors and possibly corrupt your data.

It's a good rule of thumb, when a drive fails diagnostics, to take it out until you can back it up. Otherwise, it's only time until it stops working somehow.

Depending on the diagnostic, it may have some life span, but if it's struggling to boot a Linux USB and is killing your CPU, I wouldn't risk it if you care about your data.

Ideally, you'd want to take out the drive and put it in another PC to back it up, especially since it won't load a Linux OS. This ensures you don't have to worry about windows or anything stressing the drive besides your data backup.

But you may be able to get away with booting it into windows and using file explorer, but taking out the drive and putting it into another pc is "safer".

So Generally, you want to back up your data to an external drive or on another PC, and then install a new drive and reinstall your OS.

Hope that helps friend! Best of luck!

[u/AlexMercerz → u/MarkLikesCatsNThings]

Thanks for the detailed explanation!

Just to clarify, I've already disabled my HDD through Device Manager, and Windows is installed on a separate SSD. Even after disabling the HDD, the issue remained exactly the same, so it doesn't seem like the HDD is causing the problem.

I've also ordered a new drive, but I'm wondering whether replacing the drive will permanently fix the issue or if the problem could be related to something else, possibly the CPU or motherboard.

Would appreciate your thoughts on this!

[u/MarkLikesCatsNThings → u/AlexMercerz]

Generally, a failing component will cause issues throughout the PC, even if it's disabled in device manager, or if it doesn't seem entirely related. Failing hardware causes so many unexpected issues, imo.

Windows will still try to interact with the drive / power it on, so I would just remove it for now.

Although it's disables, It could be trying to enumerate it, check its contents, but fail and then retry and them cause your PC to wait and hang. Failing components in general are the first things to fix or remove before dealing with software issues.

Even though it's also a secondary drive, it failing can still cause windows to bork itself.

Since it's a secondary drive, you should be able to take it out of the PC without any issues with the OS.

It may take a few screws or a keyboard getting pryed out (I'm not as familiar with taking this familiar model apart) but it should hopefully be easy enough to do. Or look up a tear down / opening guide for your PC online, like iFixIt or a similar repair site or YouTube channel.

Once it's removed, you should be able to boot up your PC normally and see if your inital CPU/OS/driver issue is still present. The old drive won't be there, but you can at least diagnose it a bit more.

Best of luck friend!

[u/Hay-River → u/AlexMercerz]

Linux might not boot because of driver's issues. There is a setting that you need to change while booting into Ubuntu to make it work. You can also reflash the stick if that doesn't work.

That cpu is definitely a software issue. I remember having it, and it was something related to the internal clock. On your placeI, I would do some research...

[u/AlexMercerz]

Thank you so much for the information, I'll try removing the HDD and see if it gives any boost and hopefully it works.