Question How to make sure the issue is from CPU

[khchehab]

Hello, recently whenever I turn my PC on, it just loops turning on and off with a code of 00. I have an Asus Maximus Ranger VII, I looked in the manual and looked online for the code it doesn't seem to narrow the issue. I tested the motherboard alone as suggested by several threads and it seems when I connect the motherboard alone (with the CPU and fan installed) to the power supply, it turns on fine, however after I connect the CPU connector of the power supply to the motherboard I get the issue of the board turning on and off repeatedly, and I have to stop it by switching the power supply off. Does that mean the issue is from the CPU? Is it dead and needs changing or are there more tests I can do to determine if it's from it or not?
Where I live, there are a lot of power outages and are not consistent, even though my PC is hooked to a UPS, I sometimes forget it turned on so after a while the PC just turns off by itself. I have an Asus Maximum Ranger VII motherboard with Intel 4790 and the power supply is Thermaltake Toughpower Gold 750W.
I appreciate any help or directions as to how I can determine the issue.

 

[ClockBomb]

Hi, from your testing, I would suspect that the issue is actually on your motherboard. This symptom is very common to a short on one of the CPU power MOSFETs. If you have a digital multimeter, you could check the legs of all transistors/MOSFETs for continuity (with the ground tip on the case of the motherboards' back connectors) to verify if only one of the legs have continuity. If two legs have continuity, you have an open transistor causing this issue. The transistors are usually close to the capacitors and inductors (little black boxes) around the CPU socket. Replacing SMD components can be tricky, but any competent hardware repair shop should do it easily. You could also check for any bent socket pins while you're there.

 

[khchehab]

Hi, I didn't have a multimeter and I'm not that knowledgable in using it, however, I was able to get another CPU that working on another PC, and tried it on my motherboard, I still get the same issue. I also checked the CPU socket pins and all seems to be in order. Could it be as you said @ClockBomb that it is a motherboard issue?