BD PROCHOT can't be checked, Laptop runs smoothly otherwise

[Boydan]

Hello!

I have a Lenovo Legion Y540 (1660 Ti, i7-9750H, 16GB RAM, battery was uninstalled way before my problems started). My laptop suddenly started to perfrom really bad a while ago, and long story short, I figured out that BD PROCHOT was causing the issue. After disabling it, everything went smooth, and this issue returned only occasionally. Recently (since the summer heat started) this became more frequent, and even after disabling BD PROCHOT, I still had stuttering and FPS drops. Using GPU-Z it turned out, that my GPU was also throttling, even though my temps were low (60°C) and power consumption was low (~10W). For PerfCap Reason GPU-Z showed Pwr, Thrm (always both, never only one) or Idle (when idle). I repasted the GPU and CPU, cleaned everything multiple times but the issue didn't go away.

I did a clean Windows install today, and the first thing I did after I got the desktop was to check CPU clock, which was 0.8 GHz (the same when BD PROCHOT was active) so I downloaded Throttlestop and disabled it. After that I restarted my laptop (because of some Intel driver asked me to), and the BD PROCHOT option is greyed out, and I can't activate it. Basically when my laptop boots BD PROCHOT is already active, and when I start Throttlestop it gets deactivated, and I can't activate it again unless I restart.

I did a quick benchmark (Throttlestop was running, so no BD PROCHOT) and my GPU and CPU seems fine, normal temps, normal performance, everything is as it should be.

I know that often BD PROCHOT is caused by a faulty sensor, or unnecessary manufacturer settings, but the fact that I had the GPU issue I described, makes me afraid that BD PROCHOT was triggered for a reason, and turning it off via Throttlestop could cause some actual problems.

My question is, can I test somehow if it was a legit warning (because of VRM overheating for example) or just a false trigger? Could my lack of battery or faulty AC adapter be suddenly causing this? What should I expect if it is a legit VRM overheating or battery or adapter problem?

Any advice on what to do or wheter my laptop is safe would be greatly appreciated!

PS: I had this issue for a while, and sunk days into researching and testing, so I might have left out something important. If some additional info, or pictures are needed, I will gladly provide them.

Thank you!

 

[unclewebb]

Recent versions of ThrottleStop lock out BD PROCHOT adjustment as soon as it is disabled. If you need to toggle BD PROCHOT off and then back on, you will need to use an older version of ThrottleStop. I think TS 9.6 was the last version that had this feature. The ability to toggle feature will likely return in a future ThrottleStop version.

You might need to shut down your computer to unlock BD PROCHOT. On some computers, simply rebooting might not be enough to unlock this.

the BD PROCHOT option is greyed out, and I can't activate it. Basically when my laptop boots BD PROCHOT is already active, and when I start Throttlestop it gets deactivated, and I can't activate it again unless I restart.

It sounds like this feature is working exactly as intended. Locking BD PROCHOT out prevents any software from enabling it again. This prevents BD PROCHOT throttling and ThrottleStop no longer has to continuously check a setting to see if BD PROCHOT is still disabled or not. That saves some CPU cycles for better things like playing games.

VRM overheating

If the VRM is overheating you should see a VR TEMP message in Limit Reasons. If you are not seeing that then the voltage regulators should be OK.

makes me afraid that BD PROCHOT was triggered for a reason, and turning it off via Throttlestop could cause some actual problems.

I have never heard from a user that damaged their computer because BD PROCHOT was disabled but that is always a possibility. If you believe that there is an actual problem then leave BD PROCHOT enabled. I am not willing to accept a laptop that sometimes gets locked to 400 MHz. I think that much throttling is ridiculous. The BD PROCHOT throttling scheme is over used and was not well thought out by laptop engineers.

 

[Boydan]

Thank you for the answer! I didn't realize the BD PROCHOT being greyed out was a feature, I guess I was using an older version before reinstalling Windows.
I'm not afraid disabling BD PROCHOT would damage my laptop, what I'm afraid of is that it is notifying me that something else is not working properly, and that would damage it. I'm just unsure if I should continue to sink hours into trying to figure it out, or just let it go. But I'm aware no one call tell me that, and should just figure it out myself. I might replace the thermal pads, since I still have the factory ones installed, and leave it at that. They aren't dry, but why not.
Thanks again!

 

[Boydan]

Recent versions of ThrottleStop lock out BD PROCHOT adjustment as soon as it is disabled. If you need to toggle BD PROCHOT off and then back on, you will need to use an older version of ThrottleStop. I think TS 9.6 was the last version that had this feature. The ability to toggle feature will likely return in a future ThrottleStop version.

You might need to shut down your computer to unlock BD PROCHOT. On some computers, simply rebooting might not be enough to unlock this.


It sounds like this feature is working exactly as intended. Locking BD PROCHOT out prevents any software from enabling it again. This prevents BD PROCHOT throttling and ThrottleStop no longer has to continuously check a setting to see if BD PROCHOT is still disabled or not. That saves some CPU cycles for better things like playing games.


If the VRM is overheating you should see a VR TEMP message in Limit Reasons. If you are not seeing that then the voltage regulators should be OK.


I have never heard from a user that damaged their computer because BD PROCHOT was disabled but that is always a possibility. If you believe that there is an actual problem then leave BD PROCHOT enabled. I am not willing to accept a laptop that sometimes gets locked to 400 MHz. I think that much throttling is ridiculous. The BD PROCHOT throttling scheme is over used and was not well thought out by laptop engineers.

Just an update: my CPU works fine when Throttlestop is running, but my GPU is constantly throttled again (pwr, thrm) and only for a moment does it spike back up to its rated speed. The GPU memory never gets above 200 MHz though. In throttlestop I can't see any GPU warnings in the Limits window, should I not get some warnings there?

I'm honestly out of ideas on what to do, my fans rarely even go above idle speeds, which is ok, as my GPU and CPU temps are well below where they could be (60 °C and 65 °C respectively). My GPU clock is 300 MHz, only sometimes spiking to 1800 Mhz. My GPU Memory Clock is between 100-200 MHz constantly. GPU usage is around 100% under load, and naturally with those clock speeds my performance is bad. GPU draws around 10W sometimes spiking to 30W synced up with the Clock speed. And the PerfCap constantly says Pwr, Thrm.

My fans CAN go fast, when using TS Bench, they speed up, but during regular use, they rarely do that. Also I can't control them manually with any software. I have also tried messing around with Power management settings, but nothing.

Any tips on what to do or any guesses as to what's happening would be greatly appreciated. Thank you in advance.

 

[unclewebb]

should I not get some warnings there?

The ThrottleStop Limit Reasons window only shows when the Intel CPU or Intel GPU are being throttled. Limit Reasons does not report anything when the Nvidia GPU is throttling. GPU-Z should show that information.

PerfCap constantly says Pwr, Thrm.

Some laptops set a very low thermal limit for the Nvidia GPU. Maybe you can use GPU Tweak by Asus to access the GPU thermal limit. The Nvidia GPU power limit might also be set way too low. I am not sure how to fix that problem.