[SOLVED] EZ Debug CPU light turns on randomly, PC won't boot

[mS3ven]

Hi guys,

I'm new to the forum and searched the forum for similar problems, but haven't found any thread discussing a problem like I have. That's why I opened this threat.

My problem:

I bought a new PC, at the beginning everything worked fine for some 2 weeks. After 2 weeks my PC won't boot regularly, but the EZ Debug LED CPU will turn instantly after I press the power button and the system won't boot.
CPU and system fans are nearly at full speed.
It happens randomly after I have shut down the system successfully and press the power button again - for example the very next day. Sometimes it works for several sessions in a row, but then not.
It happens nearly every time I want to restart the machine via restart in Win10. This is the only "pattern" I found out until now.

The first time it appeared, was after an unsuccessful Win10 20H2 update, which requires a re-boot. But it maybe coincidence.

I flashed the newest BIOS version and performed CMOS-Reset, nothing worked.
The only way I found out to solve the problem temporarily is if I disconnect RAM, GPU and SSD.
Then start the PC, at first the EZ Debug LED turns on for CPU, but switches from CPU to RAM. CPU & system fans slow down to normal speed.
I switch off the machine, put in the RAM, start the machine, Debug LED switches from RAM to GPU, turn off, put in GPU, Debug LED switches to SSD, turn off, connect SSD, turn on ... et voila ... system boots again.

But the system boots now a bit longer, maybe +30% and sometimes it happens that even though no EZ Debug LED turns on, the monitor won't receives any input. I need to press the power button and "forcefully" restart the machine.
Also, the Wraith Prism Cooler RGBs are overwritten (which is of course the least problem).

My HW:

• MSI B450m Mortar Max RGB
• Ryzen 7 2700x with Wraith Prism Cooler RGB, not OC
• 16GB XPG D41 RGB, not OC
• MSI GTX 1660 Super, not OC
• Crucial MX500
• Thermaltake Smart BM1 600w

My SW:

• Win10 Pro
• all latest drivers installed (BIOS, Chipset, GPU, etc.)

Do you maybe know how to help?
Many thanks in advance!

mS3ven

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[Ajfer03]

This is not a windows problem, this is hardware related. If you are getting a debug light at POST, then Windows has not even been loaded yet. It sounds like something is damaged on your motherboard, or a component like RAM, GPU, CPU, or PSU is malfunctioning. Here are a couple of things I would try.

-Check for Bent CPU pins. If you have not taken it out since OEM install, then you're fine here.
-When you get windows to boot, run stress tests on both your GPU and CPU. Do them both at the same time to stress test the PSU. Depending on which test fails will determine the failed component.
-Try a known-to-be-good PSU. While Thermaltake is an OK manufacturer, power supply defects do happen. Even if it is not the proper wattage for your system, try booting and shutting down multiple times to see if your problem persists.
-Reseat your CPU. Worth a shot.
-Remove your GPU and get into windows to see if your problem persists, again, worth a try.

Also, is the debug light blinking a specific error message? If so look it up on the manufacturer's website.
Let me know how it goes.

 

[mS3ven]

Hi Ajfer,
thanks for replying.
I did the following:

-Check for Bent CPU pins. If you have not taken it out since OEM install, then you're fine here.

The CPU wasn't touched since it was first time seated.

-When you get windows to boot, run stress tests on both your GPU and CPU. Do them both at the same time to stress test the PSU. Depending on which test fails will determine the failed component.

I run the following stress test:

• CPU: Prime95 (and RAM was stress-tested as well)
• GPU: Heaven Benchmark 4.0

I tested both simultaneously for 15min. Nothing happened. Was the test too short, should I use other stress tests?
I monitored it with HWINFO64, everything was OK.

-Try a known-to-be-good PSU. While Thermaltake is an OK manufacturer, power supply defects do happen. Even if it is not the proper wattage for your system, try booting and shutting down multiple times to see if your problem persists.

Unfortunately, I don't have another PSU, however I was shutting down the system and restarting it, with no effect (this time ...)

-Reseat your CPU. Worth a shot.

Have done so.

-Remove your GPU and get into windows to see if your problem persists, again, worth a try.

My mainboard doesn't have onboard graphics, so if I remove the GPU, I can't get into windows. The EZ Debug LED then turns on for the GPU and won't go any further.

Also, is the debug light blinking a specific error message? If so look it up on the manufacturer's website.

No, the LED isn't blinking.

I will monitor it from now on, maybe something helped. I will come back, if I got stuck again.
Many thanks!

 

[Ajfer03]

No problem, if this seemed to have solved it for you, just be sure to mark my reply as "Best Answer". It reflects on my profile. Good luck!

 

[Ajfer03]

Also, for a stress test, I would recommend downloading FurMark. It is a for-sure way to fully stress all components to the max on your PC. Its pretty simple too.

 

[mS3ven]

Hi, unfortunately the PC got stuck again. This time after putting it into Sleep Mode.
However, now my “workaround” isn’t working anymore ...

Again, the same:
CPU LED is turned on, and PC won’t boot ...