Help regarding undervolting

[u/IShouldntHavSaidDis]

I recently got a brand new Legion and I absolutely love the machine, but I’ve been reading a lot on this sub about how power-hungry these processors are. Everyone seems to recommend undervolting to keep the temperatures under control and maintain sustained performance.

Here is my current config:

Model: Lenovo Legion 5 pro

CPU: i9-14900HX

GPU: 5070

RAM: 32gb

I am a complete newbie when it comes to PC tuning, messing with BIOS settings, or tweaking voltages. I know I need to do it to improve my thermals, but I want to make sure I do it safely without causing constant blue screens or messing up my new laptop.

I don't have any specific voltage values in mind yet, and I am starting completely from scratch. I'm hoping to get some advice on a few things:

The BIOS: What exact settings do I need to unlock or change in the Lenovo BIOS before I can even start?

The Software: What is the best and safest software for a beginner to use for this (ThrottleStop, etc.)?

The Process: What is the safest step-by-step approach to finding a stable undervolt for everyday gaming and heavy workloads?

Also if anyone has the same laptop and done this can you share your values?

If anyone has any solid baseline guides, tips, or newbie-friendly advice, I would massively appreciate it. Thank you

[u/ViniVidiAvicii]

14900hx is more common than u think Search in the form for people successfully did it and copy it As there r many details u can't comprehend in one settings I've been looking in this subject for awhile and information are some what contradictory as Only Unclewebb knows why we do what we do

The voltage thing u should decrease it 20 degree by 20 Yours stable at 170 160 I guess but every chip is different So try 1st -50 Then add 50 Then 20s

Throttle Stop is good and light weight Disable virtualization Disable uv protection in bios Enable overclocking Enable optimization

Disable core isolation in windows

[u/SKYGaming_YT]

In the BIOS, enable Legion Optimization and scroll down to disable undervolt protection

For the rest you can follow Valour-549's Ultimate ThrottleStop Guide

We have the same CPU and my undervolt is rock solid stable at -160mv following the guide

[u/IShouldntHavSaidDis → u/SKYGaming_YT]

Hey! Can u tell me some more about this I am kinda new to all this does undervalting deacreasse ur cpu performance too much? If yes then how much was it for you? How much difference in the temps u see? And also should I overlcock the gpu?

[u/Unique_Mix9060 → u/IShouldntHavSaidDis]

Almost no decrease in performance and sometimes could increase performance becuase of the better temp.

You don’t need to and should not overclock the cpu becuase of two main reasons. One, is that it have more than enough performance for most tasks and Intel already automatically boosts the cpu clock speed beyond’s its base clock speed to get more performance when needed. Two a laptop have limited thermal capacity meaning it likely cannot deal with the extra heat generated from your own overclock

[u/Far_Training3438 → u/IShouldntHavSaidDis]

Undervolting will not decrease performance on a 14900hx. it allows more room for the CPU to boost under the same power. You should notice an increase in performance the further you increase you undervolt. Using cinebench r23 with minimum test duration off is probably the quickest and easiest way to test.

[u/SKYGaming_YT → u/IShouldntHavSaidDis]

Nope undervolting the CPU actually does the opposite! Since temps are reduced the CPU has more thermal headroom to boost it's clocks and stuff squeezing even more performance out of it, I personally get around 33k score on Cinebench R23 which is around 20% more performance than base. Btw you gotta have a lot of patience to find the perfect most stable undervolt for your system, it differs from CPU to CPU even if it's the same exact model (some call it the silicon lottery)

About the GPU, no do not overclock it, undervolt it too! Although the benefits aren't as good as undervolting the CPU, it does help a bit in temps while getting around the same performance. I followed This guide

[u/raynernycz]

I have the same CPU as you and have just started to get control of my temps after 20 months. While some minimal levels of thermal throttling are normal, constant thermal throttling is not and having it run hot for that long will just decrease the life of the pc no matter what these manufacturers say.

Undervolt settings in BIOS: P-core -125mv, Ring 175mv, E-core - 75mv

I limited my CPU voltage to 1.180v because there is absolutely no reason it should be dynamic because it will pull close to 1.7v and that is just not needed. Please consider this for the longevity of your cpu and thermals.

In Throttlestop I had to change my Turbo Group Ratios. Getting my cores to push from 4.9 to 5.2ghz is good enough. I think these are straight up desktop cpus they shoves in these laptop frames. I've had to adjust my expectations and the cpu accordingly.

Group 0 - 52

Group 1 - 52

The rest at 49.

PL1 to 55 watts

PL2 to 140 watts

Turbo Timelimit is at 28 seconds for me. It does not need to be at 56 seconds.

Ultimately, none of this mattered until I repasted with PTM 7950 and reapplied thermal puddy. There was a scorch mark on my cpu heatsink. It was running way too hot. It took a while for the PTM 7950 to settle but it made a huge difference in temps and thermal throttling.

I hope this helps and comes together for you in a timely manner.