Throttling on i5 - 8250u

[Ermaris]

Hello.

I have a lenovo 81C7 laptop: Win 11 home i5 - 8250u, 12GB RAM, Radeon RX 560 Series 4GB and I only use it to stream Xbox video to Twitch via obs when streaming.

As you can see in the "limit reasons" window when OBS is running, a lot of problems occur. OBS is set to stream through the CPU, not the graphics card, because it doesn't make it.

I wanted to improve the CPU performance by Throttlestop, but undervolting didn't help anything. Usually, during streaming, the CPU is loaded to about 70% until, for no reason at all, the CPU suddenly goes into a state of using 100% - then the sound and video starts to interrupt heavily and the laptop runs unstably. Unfortunately I was not able to record this on the Log I inserted.

When I checked the various undervolting options during the Cinebench20 test, the temperatures stayed at 70 degrees max, and the clock drops to 2000Mhz - In the limit reasons glowed red PL1 and EDP OTHER.

Please help, I would like to find the right Throttlestop settings for my CPU so that it runs stable and allows streaming without problems.

I'm posting screenshots and LOG file of several minutes stream.

 

[AleXXX666]

maybe repaste it properly with Arctic MX5? 8250U is not new cpu...

 

[Ermaris]

The paste was replaced half a year ago. maybe I don't know, but it seems to me that it could be power throttling. I don't know what I can do to stabilize the processor under load.

 

[unclewebb]

To try and fix a power limit throttling problem, open the TPL window and check the MMIO Lock box near the top right of this window.

Clear the Disable Controls check box. Set Long Power PL1 and Short Power PL2 both to 25W. Leave the turbo time limit at 28 seconds. Your cooling can only handle about 25W so I would not set the power limits much higher than this.

On the main ThrottleStop screen clear the BD PROCHOT box. Leaving this box checked can cause severe throttling on some Lenovo laptops.

The paste was replaced half a year ago.

What thermal paste did you use? Some thermal pastes that are popular on desktop CPUs are not suitable when used direct die on a laptop CPU. They can start to degrade or fail in as little as a week.

and allows streaming without problems

Intel's low power mobile U series processors were never intended to be used for any significant and consistent loads. The cooling solutions are barely adequate for this. Hopefully the suggestions above can help. Post an updated log file.

 

[Ermaris]

I changed the Offset Voltage to -80.1mV. The settings you provided improved the CPU performance in Cinebench20. Stream also works better but still EDP OTHER lights up red under load.

What thermal paste did you use? Some thermal pastes that are popular on desktop CPUs are not suitable when used direct die on a laptop CPU. They can start to degrade or fail in as little as a week.

I had the thermal paste changed at a computer service center, I didn't do it myself so I don't know what kind.

I'm wondering about Limit Reasons for Core and GPU - for Idle the PL1 and PL2 lights glow yellow in both columns - CORE and GPU. During load during stream, EDP OTHER in RING and PL2 in CORE column blink red, the rest remains yellow.

I attach the Log File from the stream.

 

[unclewebb]

Did you set PL1 and PL2 to 25W? Post an updated TPL screenshot so I can double check your new settings.

Your CPU is still power limit throttling at approximately 18W. Some laptops use an embedded controller (EC) to enforce a lower power limit. ThrottleStop has no control over the EC. If you followed my previous advice then you are not going to be able to solve this power limit throttling problem.

 

[Ermaris]

Did you set PL1 and PL2 to 25W? Post an updated TPL screenshot so I can double check your new settings.

Yes of course, as you see 25W is set.


Is it possible to bypass EC, or do something else to get rid of Throtling?

 

[unclewebb]

Some people have changed the IMON Slope variable in the BIOS. This trick can be used so the CPU reports half as much power consumption. This can help get around some power limit throttling problems.

I have never done this so you will need to do some IMON Slope Google research.

 

[Geoluread]

I have a lenovo ideapad 330S-15IKB, same cpu and gpu is intel uhd 620. I've been trying to get risk of rain 2 to run smoothly at any settings possible for the better part of a week and today I got good results (best time for 120 TS bench is 18.546, but usually closer to 19.2), but I am in no way an expert so take everything I say with a grain of salt.

I might've been lucky that my laptop was compliant in letting TS do whatever it wanted, but these are the main things I would consider trying if you are still looking for answers:

Spoiler: TS MAIN MENU

In the main menu, check the box that says "SpeedShift" and lower the number from 128. The closer to 0 it is, the more the cpu will disregard energy.

Change your windows power plan and customize it for maximum performance. Then, select "High Performance" from the dropdown in the TS main menu.

The number next to "Set Multiplier" in the TS main menu is 16 for you, but for me it's 34. I can't change it and I don't know how it got that way, but I would look into that.

Spoiler: FIVR

Keep in mind that an undervolt that is stable under high loads may not be stable at high loads AND temperatures (~95 C), OR when an abrupt change in voltage happens. I had the "Alarm" box checked in options, and it was causing premature crashes because it would change to a power saving profile before the adaptive voltage could adjust. Throughout the past week, my computer must have crashed AT LEAST 20 times and it's still fine, so it can't be that dangerous, right?

EDP Other under Ring and PL2 under Core will be red even if you're at 25 W. I managed to get EDP Other to only be red sometimes by unchecking "Ring Down Bin" in FIVR, but it made the cpu perform less consistently. Lowering the Cache Ratio gave similar results. Maybe they will work better for you.

Contrary to it's name, "Thermal Velocity Boost" actually weakens your cpu once you pass a certain temperature. The effect is very small, though, and I can't say it worked all the time even when it was on.

You can turn "IccMax" to the maximum, but I don't think it will help unless you are current limited, which my cpu never was.

Spoiler: TPL

I think checking "Speedshift" improves performance, but not 100% sure.

I'm not sure what clamp, power balance, TDP level, or PP0 limit do. Power balance might only apply if you're using an igpu, which I am.

In my log, around 6:30 pm is when I started playing. BDPROCHOT activated at some point but I don't know when, but I could feel the gpu heating up from the keyboard. I'm curious about what the other settings do, especially power balance, to see if I can squeeze out a bit more performance.[/SPOILER][/SPOILER]

 

[unclewebb]

   DATE       TIME    MULTI   C0%   CKMOD  BAT_mW  TEMP    VID   POWER
2023-09-01  18:04:00  33.99   13.4  100.0       0   55   1.0078    8.9
2023-09-01  18:04:01  33.95   13.7  100.0       0   64   1.0121    9.2
2023-09-01  18:04:02  34.00   15.5  100.0       0   55   1.0098    9.8
2023-09-01  18:04:03  34.00   16.9  100.0       0   57   1.0277   10.3
2023-09-01  18:04:04  34.00   13.4  100.0       0   59   1.0248    8.8
2023-09-01  18:04:05  34.00   14.4  100.0       0   62   1.0255    9.0
2023-09-01  18:04:06  34.00   15.0  100.0       0   61   1.0082    9.3
2023-09-01  18:04:11  10.23   42.4  100.0       0   47   0.5372    3.7   TEMP
2023-09-01  18:04:11   4.00   43.4  100.0       0   47   0.5372    2.5   TEMP
2023-09-01  18:04:12   4.00   44.6  100.0       0   47   0.5377    2.5   TEMP
2023-09-01  18:04:13   4.00   44.3  100.0       0   47   0.5377    2.5   TEMP
2023-09-01  18:04:14   4.00   41.3  100.0       0   47   0.5377    2.5   TEMP
2023-09-01  18:04:15   4.00   44.8  100.0       0   46   0.5372    2.5   TEMP

This part of your log file shows that TEMP (thermal throttling) is the reason your CPU is being forced to run at its minimum speed. This does not appear to be BD PROCHOT related. Many Lenovo laptops lower the thermal throttling temperature to absurdly low values. You need to check the Lock PROCHOT Offset box in the Options window to prevent this type of throttling. If you have any random shut downs at or near 100°C then I would set PROCHOT Offset to about 3 to try and prevent any random shut downs.

Intel programs their CPUs to do a thermal shutdown at approximately 125°C. Some manufacturers decided that this was too high and are using a 100°C shutdown temperature instead. If this is the case, you need to adjust PROCHOT Offset to prevent this from happening. When PROCHOT Offset is locked, you need to reboot when making any changes to the PROCHOT Offset value.

I would clear the BD PROCHOT box on the main screen of ThrottleStop.

Your laptop cooling system can dissipate about 20W to 22W. Setting the power limits to 25W will work for a while but ultimately, this leads to thermal throttling because the cooling system cannot keep up. If you can find a magic way to improve cooling, you could run your CPU at a higher power and performance level. Without better cooling, you will be constantly living on the edge of either power limit throttling or thermal throttling.