Issues with MAG X870 Tomahawk

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reaktiiv15be02f1

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Cheers,

  • I just recently upgraded my rig with Tomahawk, 9850X3D and Kingston DDR5. After clean installation of the operating system and starting to use the new hardware, I have faced some issues that I never had before. The issues are:

1) The PC won't completely turn off when I shut it down. The monitors go black but lights stay on on the GPU and case fans.

2) During desktop use, my CPU temps are around 45 C which is ok. When gaming, the temps have been on average around 65 C, which is also ok. However, after I stop gaming and return to desktop, the gaming temps remain for as long as I shut down the PC. For example, if I quit the game to desktop and leave the pc on idle, the temperature won't drop but is still around 65 degrees, no matter how long I give the PC time to "cool down".

3) On couple of occasions, the CPU temps have remained at solid 45 C no matter what I have done - desktop or intensive gaming. I have checked the temperature on the onboard LCD display and using HWMonitor, and it is probably correct as on these occasions the fans have not increased their RPM like they usually do under load.

So far what I have tried to do is:
1. Disable fast startup in Windows - no effect.
2. Enable and disable ErP ready mode - no effect.
3. Updated BIOS and chipset drivers to latest - effortless installation but no effect on the problems.

What should I do? Is this just a driver/software related problem, or is there a chance the hardware is faulty?

Thanks.
 
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reaktiiv15be02f1 said:
Nope, non-E as the headline suggests.
Click to expand...
Welp, this is the first time i heard about a non E having the same issues, you can see how many people are facing the same trouble, and all none of them could manage to fix it, its possible to reproduce it easily, here, i will even copy pasta my report that i sent msi, i dont think the temperature locking in low will be an issue, since this only occurs when cpu usage is high so as high temp, im waiting till next week so i can buy another board and send this one to them since i doubt it can be fixed by bios updates




Below is an objective and chronological technical report for analysis of a recurring failure related to CPU power delivery / power management under sustained high load.



General Context​


The system operates normally under idle and light workloads, but becomes unstable under high and sustained CPU load, both in synthetic stress tests (OCCT AVX-512) and in real-world usage, including intensive games such as Path of Exile 2, after a certain amount of runtime.


The issue is not immediate; it occurs progressively and reproducibly, depending on how long the CPU remains under load.


OCCT was used to reproduce the same scenario that occurs after hours of regular gaming. Tests were conducted consistently using Extreme mode, Variable load type, and AVX-512 instructions, which allow the issue to manifest more quickly. As extensively documented, AVX-512 is particularly suitable for diagnosing sensor-related issues.



Observed Behavior​


In all failure scenarios, the behavior is consistent:


  • CPU Package Power (CPU Package / PPT as reported by motherboard sensors) abruptly drops to 0W
  • Motherboard monitoring sensors freeze
  • Motherboard diagnostic LED becomes stuck
  • The system remains powered on but enters an inconsistent state; when attempting to shut it down, both monitors turn off, fans continue spinning, and the system does not power off properly
  • A forced reboot is required to then perform a full shutdown
  • No clean shutdown or automatic reboot occurs


Tests Performed​


1. Initial State​


  • BIOS updated to the latest available version
  • System running at default settings
  • EXPO initially enabled (later disabled for testing)
  • No manual overclock or voltage adjustments

Result:
MSI Afterburner began freezing and becoming unresponsive (HWINFO exhibited the same behavior). These issues were partially mitigated by reverting to BIOS A33, which is recommended in discussions on the official MSI forum as a more stable BIOS version.


Failure occurred in under 2 minutes during OCCT AVX-512, with CPU Package Power dropping to 0W.



2. Clear CMOS + Clean BIOS Configuration​


  • Clear CMOS performed correctly
  • BIOS reset to default settings
  • EXPO disabled
  • PBO and all automatic boosting features disabled
  • BIOS reflashed again to the same version to ensure firmware integrity
  • LED firmware reflashed as instructed by an MSI Global moderator
  • All monitoring software closed; Windows environment kept completely clean

Result:
The system was able to sustain load for a longer period:


  • OCCT AVX-512 stable for 46 to 58 minutes
  • CPU Package Power stabilized around 140 W
  • Temperature stabilized at approximately 85 °C

However, after ~58 minutes, the failure reoccurred with the same symptoms:


  • CPU Package Power dropping to 0W
  • Sensors and diagnostic LED freezing


Relevant Observations​


  • Clear CMOS increased time to failure but did not resolve the issue
  • The issue occurs with EXPO disabled
  • The issue occurs without any overclock
  • The issue occurs in both synthetic testing and real-world workloads
  • The issue is fully reproducible
  • The power supply is new, appropriately rated, and shows no instability in any other scenario
  • As an additional diagnostic step, the CPU and PSU were tested separately in another fully functional system by a trusted technician, where they remained under load for approximately 24 hours without any instability, sensor freezes, or Package Power drops
 
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Too many people have reported this issue (maybe everyone has it but doesn’t realize it), so if you decided to replace the motherboard you’d have a high chance of ending up with another defective one.
The fact that the issue affects different motherboard models is also a sign that this is a software problem rather than a hardware one.
Still, it’s worth trying.
 
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michelelaurell152d02d4 said:
Yes, the same to me
Click to expand...
From Google it says this.

"Check Internal RGB/Fan Connectors
If you have a dedicated fan controller or RGB hub, it might be receiving 5V standby power directly from the PSU, bypassing the motherboard's power management. You may need to move the power source for these devices to a different header."

I have 2 corsair RGB hubs. Anyone else with the issue have RGB hubs?
 
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anthony.angio152b02d7 said:
From Google it says this.

"Check Internal RGB/Fan Connectors
If you have a dedicated fan controller or RGB hub, it might be receiving 5V standby power directly from the PSU, bypassing the motherboard's power management. You may need to move the power source for these devices to a different header."

I have 2 corsair RGB hubs. Anyone else with the issue have RGB hubs?
Click to expand...
I have Corsair Titan 360 RX RGB and Corsair iCUE 5000T LX RGB
 
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Corsair iCue is known to cause issues, although the latest version works flawless on my tomahawk x870 with the K55 RGB keyboard.
In my case it crashed windows. Anyway, to rule it out it's best to remove all iCue software and use hwinfo64 for readings.
As for everyone having it without realising, no, I don't have it yet and my system is over 1 year old now. And I run all my games with afterburner osd combined with hwinfo64 osd to include all my fan speed readings. I'm used having it in the top right corner, and for the few games that have the ui in that corner I switch it to the left. In the beginning I used an exsisting win10 install from a previous intel board and it worked flawless, later made a dual boot with win11 and all is still fine, due to multiple mbr records in bios I had to reinstall win10 and fixboot/bootrec/bcdedit everything to normal. But that has nothing to do with the topics issue.
 
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tfbisqui156f02d4 said:
Corsair iCue is known to cause issues, although the latest version works flawless on my tomahawk x870 with the K55 RGB keyboard.
In my case it crashed windows. Anyway, to rule it out it's best to remove all iCue software and use hwinfo64 for readings.
As for everyone having it without realising, no, I don't have it yet and my system is over 1 year old now. And I run all my games with afterburner osd combined with hwinfo64 osd to include all my fan speed readings. I'm used having it in the top right corner, and for the few games that have the ui in that corner I switch it to the left. In the beginning I used an exsisting win10 install from a previous intel board and it worked flawless, later made a dual boot with win11 and all is still fine, due to multiple mbr records in bios I had to reinstall win10 and fixboot/bootrec/bcdedit everything to normal. But that has nothing to do with the topics issue.
Click to expand...
Try the OCCT cpu stress test. 2-3 times, 30 minutes, shut down the computer after each attempt. You will see the CPU package power to 0.
 
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Why should I do that? I ran it for an hour 2 times in a row, stressed the system in all possible ways. Play a game and let it run for half a day, ofcourse walking away several times for eating, or watching a brief item on TV. I switch forth and back from the menu in those instances for not interrupting my game progress, alt\tab frequently to check something on YouTube etc etc. And when I switch of my PC after 12 or more hours all sensors are still working fine. Without a soft reboot. So no, just as in a previous discussion about this, not everyone is experiencing what you are. This is not a structural problem or else MSI would already adress it.
 
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tfbisqui156f02d4 said:
Why should I do that? I ran it for an hour 2 times in a row, stressed the system in all possible ways. Play a game and let it run for half a day, ofcourse walking away several times for eating, or watching a brief item on TV. I switch forth and back from the menu in those instances for not interrupting my game progress, alt\tab frequently to check something on YouTube etc etc. And when I switch of my PC after 12 or more hours all sensors are still working fine. Without a soft reboot. So no, just as in a previous discussion about this, not everyone is experiencing what you are. This is not a structural problem or else MSI would already adress it.
Click to expand...
This problem happens when the CPU is at 100%, and on some startups it may not happen at all. If you’re gaming or watching YouTube, etc., the CPU never reaches 100%
 
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tfbisqui156f02d4 said:
Why should I do that? I ran it for an hour 2 times in a row, stressed the system in all possible ways. Play a game and let it run for half a day, ofcourse walking away several times for eating, or watching a brief item on TV. I switch forth and back from the menu in those instances for not interrupting my game progress, alt\tab frequently to check something on YouTube etc etc. And when I switch of my PC after 12 or more hours all sensors are still working fine. Without a soft reboot. So no, just as in a previous discussion about this, not everyone is experiencing what you are. This is not a structural problem or else MSI would already adress it.
Click to expand...
It's a bad batch of motherboards then that a BIOS update probably can't resolve. As I got all my components brand new from Argos and I've seen multiple people get a different motherboard and it worked fine. I'm opting for Asus since I never had problems with them, B850-F i'll order when I can.
 
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anthony.angio152b02d7 said:
It's a bad batch of motherboards then that a BIOS update probably can't resolve. As I got all my components brand new from Argos and I've seen multiple people get a different motherboard and it worked fine. I'm opting for Asus since I never had problems with them, B850-F i'll order when I can.
Click to expand...
It's a too big batch of motherboards. I'm quite sure that it's on all motherboards if everyone does the stress test correctly.
 
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