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Help controlling temps on Asrock Z790 lightning (DDR5) and 13900K CPU.

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New Member
Feb 8, 2023
I recently purchased this new PC ( Arrived in January), an upgrade from an 8700K with an MSI mboard.
I know nothing about the AsRock motherboards and am having a hard time finding anyone who DOES know.

I basically want to disable the multi-core enhancements (I do not believe this is HT but on this generation Mboard I simply do not know - there is no such thing on my old MSI mboard)) limit the PL1&2 power draw to 253 watts and under-volt it by 100mv.
I got the settings above from a reddit thread in which the OP brought his temp's down to 75-85 degrees on full CPU load and increased his cine-bench score from 24K to 34K.

I have no clue where to start with that on this mboard.

Please help?
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First of all, what cooler are you using and are you confident that you removed the plastic film and properly applied thermal paste?

Second, what are your temps right now under moderate load, i.e. gaming, and full load, i.e. cinebench?

You're not going to find it running as cool as the 8700k by a long shot, but as long as it isn't throttling then you're doing alright. To really get into it, it would be preferred for you to post or add to your signature the full specs of the system (you can see my signature for an example).

Here is an article that discusses the settings you mentioned and what they actually do: https://www.pugetsystems.com/labs/a...ermals-and-content-creation-performance-2375/. If you want to restore the stock intended values (described in the article MCE off, PL1 125W, PL2 253W) and then test things out again. After that you can try increasing your PL1 or undervolting. I wouldn't recommend changing everything to the values according to one person on reddit, because each system is different. Instead you'll want to change one thing at a time and test to see the impact on your system.

Thank you very much for your response.

I use Kubuntu Linux Windows 10 temperatures are slightly higher when I boot into it. I mean by a few degrees, not a BIG difference.

I purchased this PC from a custom builder and the guy who put it together has had the business for 15-20 years.
I believe the plastic film has been removed and I believe the thermal paste was applied properly.
My cooler is an NZXT 240mm AIO and my case is an NZXT H510i with the cooler rad mounted on the front on pulling air into the case.
the case fan at the rear also pulls air in and the case fan at the top pushes air out.
The power supply is enclosed in it's own area.
The video card is horizontally mounted with a brace to keep it from sagging and damaging itself of the slot.
( https://www.amazon.ca/Graphics-Supp...=B0B1WM7LTP&psc=1&ref_=pd_bap_d_grid_rp_0_1_t )

normal usage temps range from 31-38 degrees idle depending on the core.

normal usage with multiple browser tabs and streaming YouTube are sitting at 33-48 depending on the core - right now I have 22 browser tabs open in two different Firefox windows and am getting these temps

When I run a game like Cyberpunk 2077 along with a few browser tabs and possibly a movie in VLC or a TV show streaming on Netflix I see approx. 60-80 with spikes near 100 and at least one core at 100 randomly and usually these spike last for 10-60 seconds before dropping.

Cine-bench shoots to 100 degrees and stays there until-completed - this does not seem to be an issue with the PC - IE: no alarms or functionality I can see due to the temps.
I would like to get under 90 degrees if I can though just to be safe.

Last night for example: I used handbrake on Linux to re-encoded a 4K resolution movie from HEVC 10 bit to x264 and for the next 16 minutes my CPU was at 100 degrees on at last 5 cores and between 80-90 degrees on the rest. Total over all package was recorded as 100 degrees, although I am using Kubuntu's System profiler for temp reading and I am unsure of just how accurate it is - it uses lmsensors to get the temp readings.
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I have already set the intel power defaults instead of the Asrock defaults (PL1 = 125, and PL2 = 253 - there is a button on the Asrock simple UEFI screen that simply says set intel power limits - I clicked it and it set the PL1 to 125 and the PL2 to 265?. I manually changed the PL2 to 253), defaults set and under volt of -100mv but it does not seem to have done anything as far as heavy workloads like Cine-bench or CPUz's stress CPU function. IT DID lower the average use temps - I used to be at 45-55 idle and with the under-volt I sit at 30-39 idle..
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So you're still looking for muti core enhancement? If you can find out what motherboard you have one of us can find the manual and guide you in the right direction.

Honestly though, cinebench is a decent test but it's not realistic for the typical gaming scenario. If you plan to do a lot of encoding then it makes more sense to try and get your temps down. But these things are hot and they're going to be hot. I understand not wanting to run at 100c, but you have to realize that temps are relative to the processor generation being reported. So as long as you're not throttling you shouldn't need to worry much. You have a 240 AIO in a rather constricted case, so expecting stellar cooling isn't realistic.
MCE is typically a dropdown option in the BIOS (Asus?). I don't recall that on ASRock boards though. Some have an option to set the cooler type which adjusts the power limits....but you're doing that already, it seems.

A 240mm AIO on a 13900K I fully expect to reach 100C. Mine comes close with a 3x120mm AIO (bone stock settings on Asus board). During MOST games, it sits around 70C or so......in the new COD, it can hit 90C as uses almost all the cores/threads available.

Handbrake (along with Cinebench) is another application that bangs on the cores and threads/voltage... I would expect it to throttle as well with a 240mm AIO.
Actually, that's my reply earth-dog. I posted for help on more than just these two forums also.

I ran system profiler and GPU-X at the same time the other day (after posting here) and all I gotta say is these CPU's are very odd to me.

In System profiler on Kubuntu, I have a temp reading for each core - some of them are over 90 degrees, 2-4 of them hit 100 degrees when doing certain tasks. However, with CPU-X open and right next to the System profiler window CPU-X gives me just one temp reading, which I assume is the whole package temp, of 65 degrees? I was watching a movie in VLC, had more than a few browser tabs open and was also, intermittently, running a bash script I was writing to test it. My old 8700k would do the same and be at 50-55 degrees but, I DO realize that 65 is not that hot at all.
I then incorprorated a game (Cyberpunk 2077 with DLSS and ray tracing turned on @2K@165hrz) and the temps were not as bad as the last timer I checked. This time they went to an average 70-80 degrees, with this CPU thats no bad, and hand spikes that lasted about 30 seconds to 100 degrees. These temp spikes happenbed when I staretd the game and when loading screens were happening, but general play did not see much oer 80, maybe 81 or 82 randomly.

I guess I am trying to get those cores that DO reach 100 degrees to come in under say 92 or so and I am having a REAL hard time doing so. Intel says this is perfectly fine and no harm done, but, can we trust that?

I also, still have to install the Debauer contact plate I got along with the Kryotek paste I purchased. According to DeBauer said in his videos that should lower temps by 5-10 degrees overall.

AND, one more thing - my CPU is not clocking down too far, as near as I can tell...instead of 5.8 on the most proficient cores (4 of the P-cores on my board) I might see 5.7 to 5.6 instead. The less proficient P-cores only go down to about 5.4-5.5 which is perfectly fine. I don't see the E cores clocking down at all really. I mean they bounce around a bit but are fairly steady @ 5.5 or 4.3 depending on the core.

I am more interested in preventing CPU damage than performance - for waht I do on a daily basis even 4.8 Ghz is surely enough speed for me and I haven't manually over clocked a CPU to get more speed out of it since Pentium 4's - I usually go the XMP and whatever preprogrammed OC is built into the Mboard and that's it. If this CPU didn't run so hot I wouldn't even have attemtped to undervolt it - I would just put up with temps of 85 or lower, when I saw that 100 degree temp on cine bench I kind of freaked out.
System profiler window CPU-X gives me just one temp reading, which I assume is the whole package temp, of 65 degrees?
I'd be willing to bet a lot more that it's just not accurate.

Intel says this is perfectly fine and no harm done, but, can we trust that?
Yes. The CPU thermally throttles at 100C. It will shutdown before it does damage to itself.

P-cores will always be hotter than the e-cores. The max boost for that chip you'll only see with 2 cores... and that's only with lighter loads.
You're online, how convenient:)

I am looking at hwinfo (system profiler - it uses lmsensors for temperature readings) and I count core 8-11 are at 5.8ghz, cores 0-10 / 12-15 are at 5.5Ghrz and the e cores are all at 4.3 temps - pretty much idle as I only have this browser window open right now are 31-37 except for 2 P-cores that are at 48 and 44 respectively.

Everyone, even Intel says only two cores will ever reach 5.8 GHz but I consistently see 4 of them at that speed.

Last time I checked immediately after a reboot the temps where all between 31-38 degrees.
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Perhaps I have been worrying about nothing?
Ill leave hwinfo up and check but i thought its only two at a time. Two other zets may be able to reach it, but pretty sure it's only two at a time.
Yah - I am pretty sure that I read that somewhere on Intel's website actually, and I remember thinking, not on my CPU/mboard, I got four. Here is temp/speed screens as of right now: hwinfo.png

Mine, so far, is two cores at a max of 5.8 Ghz on Asus board with MCE disabled...otherwise it's all p-cores at 5.5 GHz max and I don't do a lot of heavily multi-threaded work. I'd rather the boost on those two cores.

Maybe it's something with Linux... not sure....
"I don't do a lot of heavily multi-threaded work. I'd rather the boost on those two cores"

I assume this is because you're heavy use cases are mostly gaming which is fine.

"Maybe it's something with Linux... not sure...."

Nor am I sure - I have used Linux off and on for about 25 years but never as a a power user across the board. I am more like an illiterate user who is tech savvy enough to find out via google whats going on and am good at following expert Linux users instructions - especially these days as Linux as a Desktop is far more in-use today than it was 25 years ago so lots more information to be found with a general google search. I have also discovered that ChatGPT can tell you exactly what is going on in a code snippet - just paste on and then ask ChatGPT to explain what the following batch code is doing. I use batch but you can sue any programming language in the place of batch. Pretty dam cool!

I only recently decided to ditch Windows as much as I can (I've logged into it 2-3 times in the past 1.5 months)

Thank you very much for your response, I wish the custom PC builder I purchased this from would have told me to get a large case with a 280 or even 340 AIO but alas that did not happen.

BTW - the Asrock BIOS does detect and list the AIO as a 240/280mm cooler...I can't remember for sure but I believe it only says cooler or water cooler or AIO but it does not say NZXT or anything further.
I forgot how big the cooler was that the builder said they were installing, I believe it was the 240 and my measuring from the outside of the case (in front) says a 280 wouldn't fit - it is exactly 13 inches measuring the outside of the case from the top of the power supply compartment to the top of the PC with what seems to me like 2x 240mm fans.

EDIT: I just did the cal and apparently a 280 would fit , but it would also be very, very tight and depending on the case it might or might not go in.
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I just now had an email exchange with the seller and he said it is a kraken X63 280mm AIO in the H510i case.
Well, I feel silly, however, for the sake of future readers having similar issues:

Use an AIO control software to increase the pump speed and create a more aggressive fan curve
and that should about do it.

I was setting the fan controls in the BIOS by clicking performance button and that was it.

The place that sold the PC to me recommended the kraken AIO control software, which
led me to looking for and finding a Linux alternative and I found CoolerControl.

Using it I created a more aggressive fan curve and I increased the pump speed.
I am now playing Cyberpunk, watching a movie and have 4 browser tabs open with
CPU temps at the low to high 50's and 2 cores at 69-72 degree but no more spikes to over 90 degrees - so far anyways.

After I install the Debauer CPU contact frame and change out whatever paste the PC Builder used and apply the Kryonaut paste I am hoping for a further 7-10 degree reduction in temps.
Awesome! Glad it was something more easy.. for pumps, I just let them run as you can't hear them over the fans/chassis fans anyway...