Help undervolting Lenovo X280 with i5-8350U

[gozep]

Should i change any of these settings before trying to reduce voltage of cpu?
3 image are at idle
4 image while TS bench
Whats the difference between decreasing Turbo power limits and Turbo ratio limits?

 

[unclewebb]

Whats the difference between decreasing Turbo power limits and Turbo ratio limits?

The turbo power limits control the maximum amount of power the CPU can use and the turbo ratio limits control the maximum speed of the CPU. Do not be afraid to do some hands on testing. You can change either of these while the CPU is loaded

Should i change any of these settings

I always check the MMIO Lock box in the TPL window. After that you can clear the Disable Controls box and adjust the MSR power limits. I find it is easier to only have to adjust one set of turbo power limits.

Your Lenovo laptop has locked Power Limit 4 to a value of 71. This will likely cause EDP throttling.

Setting the core and the cache to a negative offset voltage of -75 mV is a good place to start testing. The U series CPUs are already low power CPUs so usually there is not as much room to undervolt them.

 

[gozep]

I only thought of undervolting, to decrease heat and loud fan.
I found some tweaks in other peoples threads with lenovo laptops and 8th gen processors.
I tried testing with cinebench, but it wont finish in 10 mins, rather in 15-20mins.

1.How do i check if this makes any improvements? Is there any tweaks i shouldnt have done?
2. How to know how much W my cooling can handle?
3.Thats what i changed so far:
MAIN:

1. Balanced performance mode - checked

OPTIONS:

1. Prochot offset 3 - checked
2. Lock Prochot offset - checked

TPL:

1. MMIO lock - checked
2. Disable Controls - unchecked
3. PL1 - 25 / CLAMP checked
4. PL2 - 30 / CLAMP checked
5. Turbo time limit - 8
6. Power limit 4 lock - min 71 / max 0, unchecked

FIVR:

1. Offset Voltage: Core and Cache -100mV
2. Offset Voltage: Intel GPU and Unslice-50mV
3. Core, Cache, Intel GPU, Unlsice - IccMax set to max, 255.75

Also attaching log file with these settings

 

[Natcuber]

I only thought of undervolting, to decrease heat and loud fan.
I found some tweaks in other peoples threads with lenovo laptops and 8th gen processors.
I tried testing with cinebench, but it wont finish in 10 mins, rather in 15-20mins.

1.How do i check if this makes any improvements? Is there any tweaks i shouldnt have done?
2. How to know how much W my cooling can handle?
3.Thats what i changed so far:
MAIN:

1. Balanced performance mode - checked

OPTIONS:

1. Prochot offset 3 - checked
2. Lock Prochot offset - checked

TPL:

1. MMIO lock - checked
2. Disable Controls - unchecked
3. PL1 - 25 / CLAMP checked
4. PL2 - 30 / CLAMP checked
5. Turbo time limit - 8
6. Power limit 4 lock - min 71 / max 0, unchecked

FIVR:

1. Offset Voltage: Core and Cache -100mV
2. Offset Voltage: Intel GPU and Unslice-50mV
3. Core, Cache, Intel GPU, Unlsice - IccMax set to max, 255.75

Also attaching log file with these settings

I also have an i5-8350u. Use Throttlestop's built in benchmark (TSbench) to compare your scores with and without undervolt, and compare the scores in Cinebench. I used to get a score of about 3300 in Cinebench, and now I can get about 4100. For TSbench, I can get about 21 or below that for 8 threads and 120m.