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:
[...] 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.
Click to expand...

On my MAG X870E Tomahawk board I have had issues exactly like you are describing, I have been playing with different combinations of settings for a couple weeks now (hint: it's not software-related in my case) to try and pin down the ultimate cause of my CPU sensor bug as it sometimes takes a bit of time for it to manifest itself when it happens, usually if I play a game that gets the hardware good and hot, and yes I absolutely keep hwinfo64 open so I know precisely when it happens.

I believe I may have it narrowed down to an issue with EXPO being set to enabled, at least in my case, either the secondaries are too tight or something else may be going on regarding it is my theory, but I am still doing testing to confirm the cause.
If I go in and manually set the identical clock speed and primary timings along with voltages (SOC @1.15v, DRAM @ 1.35v) then let memory training handle the rest of them, I have not had it recur... so far.

I am running 32gb(2x16) 6000mhz g.skill flare x5 @ 36-36-36-36-96 (all the rest Auto), PBO advanced with Auto limits, -15 on all lesser cores -10 on the 4 best.

When my sensor bug does manage to occur, the CPU temp reading locks in place and the CPU stays strictly in its high-power mode, but the fans also stop adjusting their speeds even if the thermals physically do go higher, so be cautious about the temperature not changing... luckily I have mine on water.

I hope some of this information helps, maybe if we're lucky enough it's just a BIOS issue that needs addressing and not a hardware one.
 
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Thanks for the reply, it is always useful to learn of peer experiences.

According to some more testing, the issues 1) and 2) are connected: if I don't use the PC for some heavy tasks (such as gaming), it turns itself completely off just fine. However, each time the temperature locking happens, the shut down issue occurs as well.

Today while testing gaming, the CPU temperature reached 87 degrees according to the mobo LCD and HWMonitor. After this, the temperature never went down, but remained at that 87 degrees throughout the whole gaming session and also while idling in desktop. To solve the issue, I had to reboot.

Of course, the real demand from the CPU would not require its temperature to remain at steady 87 degrees all the time, not even during gaming, since the temp should fluctuate all the time following the load. Thinking rationally, the problem is probably one of the following:

1) The CPU enters a solid high-performance state and keeps the clocks running high, and it remains there regardless of the actual performance required from the CPU.
2) After reaching the peak temperature, the CPU sends temperature monitoring signal according to the high temperature, which is then displayed by the LCD and HWMonitor, and the fans adjust their RPM accordingly (even if the real CPU temperature is not the same as the one that is being displayed).

Got to do some more testing with the EXPO settings. However, since EXPO improves the gaming efficiency and FPS significantly, it is not an option to leave it disabled even though it would fix the problem. Can we trust that there will be an update fixing this issue, or should I appeal for warranty?
 
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anthony.angio152b02d7 said:
Could it have something to do with sprectrum spread being set to auto as some boots I can last ages playing games and it's fine and some boots it drops to 0w quite quickly.
Click to expand...
I have disabled both spread spectrum and DRAM power down as well as any other power saving features (ErP) I could find to eliminate fluctuations/inconsistencies that could potentially contribute to the issue, though I didn't notice a massive drop in frequency of occurrence on my setup until after I turned the "EXPO" setting off and just started manually setting most of the primary timings, speed and voltage to match EXPO as well as limiting the SOC voltage to <=1.2v.
 
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I mean, this behavior could probably be harmful for the CPU especially in the long run. If the temperature lock-in happens at a relatively low temperature, then the cooling effect of the fans is not sufficient to keep the CPU cooled when under heavy load, potentially leading to the overheating of the CPU. There shall be a fix to this issue rather sooner than later. I will also consider my options to return the mobo and try my luck with another brand. Shame, as otherwise I really took liking to this one.
 
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reaktiiv15be02f1 said:
I mean, this behavior could probably be harmful for the CPU especially in the long run. If the temperature lock-in happens at a relatively low temperature, then the cooling effect of the fans is not sufficient to keep the CPU cooled when under heavy load, potentially leading to the overheating of the CPU. There shall be a fix to this issue rather sooner than later. I will also consider my options to return the mobo and try my luck with another brand. Shame, as otherwise I really took liking to this one.
Click to expand...

During the stress test, the CPU temperature goes up to around 90 °C and the fan speed increases accordingly. After a while, the temperature reading appears to freeze, but once the stress test ends, the fan speed immediately returns to normal. This indicates that the motherboard is still able to correctly read and communicate the actual CPU temperature. The CPU is always being properly cooled. I am using Corsair iCUE software.
 
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reaktiiv15be02f1 said:
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.
Click to expand...
btw your board is the E variant right?
 
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michelelaurell152d02d4 said:
During the stress test, the CPU temperature goes up to around 90 °C and the fan speed increases accordingly. After a while, the temperature reading appears to freeze, but once the stress test ends, the fan speed immediately returns to normal. This indicates that the motherboard is still able to correctly read and communicate the actual CPU temperature. The CPU is always being properly cooled. I am using Corsair iCUE software.
Click to expand...
For me, the fan RPMs lock in place too in accordance with the CPU temperature. So for example, if the temperature locks in a high temperature value, the fans rotate with high RPMs which is distinctive by the louder noise. When I return to deskop, the fans keep this high RPM until I reboot. For this reason I assume that if the lock-im temperature is low, the cooling may not be sufficient for the CPU under heavy load.
 
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