[SOLVED] Lenovo Y540 throttling even with good thermals

[dhruvky94]

Hey guys,

I recently got a Lenovo Y540 laptop with i7 9750H and RTX 2060. I tried to run Witcher 3 and AC:Odyssey on it and found the temps were too high (95c).

So I started tweaking it... First updated the bios and all the drivers. Post that, started undervolting using INTEL XTU. Looks like it changed something because after that I undervolted to -.150 and underclocked and it was working fine. The only issue was that XTU was resetting clocks frequently.

So I switched to Throttlestop and uninstalled XTU while restoring to default profile. After doing the same settings, I was getting good thermals in both CPU and GPU but I was still getting throttling (to 800 MHZ) in games due to "BD PROCHOT".

Now I know, I can just disable this but many people online have warned against it and I don't understand why it's throttling even though my temps are good. I am running on Lenovo performance mode as well as plugged in. As I understand there could be some other component that is running hot but I don't which one. I did an update of Intel Thermal framework so not sure if that could be an issue?

Edit: I am running on lates bios and software. AIDA64 is running fine but during gaming laptop is throttling.

 

[dhruvky94]

Upon further deep dive, I saw that all my components are showing good max temps. PCH is max 72c (not sure if it's high). I did see that my graphics car is power throttling but CPU always shows "BD PROCHOT". Can PD PROCHOT occur due to power limit throttling?

 

[zx128k]

Processor Hot (PROCHOT) throttling signals happen within the processor. You need to troubleshoot why your CPU is overheating.

 

[dhruvky94]

Processor Hot (PROCHOT) throttling signals happen within the processor. You need to troubleshoot why your CPU is overheating.

Thanks for replying!
It is not PROCHOT that is getting triggered, it's BD PROCHOT. It is for bi-directional , i.e. if some other component in signaling CPU to throttle because of heat. However, all my other components are fine and have good thermals.
GPU is getting power and voltage throttled though. Here are some pics showcasing the issue:

https://imgur.com/a/yxdhpsS

View: http://imgur.com/gallery/yxdhpsS
and

https://imgur.com/a/2BuSvn7

View: http://imgur.com/gallery/2BuSvn7
.

 

[zx128k]

BD PROCHOT stands for “Bidirectional processor hot.” ‘Bidirectional’ refers to the fact that this signal can be thrown by the CPU itself (to lower its own temperature) or by another component as a means of protecting that part from overheating. Imagine, for example, that your GPU was going to overheat and damage itself due to high operating temperature. The GPU can throw this flag to reduce the CPU’s frequency, reducing the processing work that was causing an overheat in the first place. https://www.extremetech.com/computi...ace-book-2-users-running-at-pentium-ii-speeds

So check all temps, including cpu, gpu, vrms etc.

 

[dhruvky94]

Hi All,

Thanks for taking the time to reply to this post. I was able to figure out the root cause for this, it was due to power throttling of GPU. I was able to fix this as documented here: View: https://www.reddit.com/r/Lenovo/comments/ghk5n5/simple_guide_to_fix_non_thermal_throttling_in/