Asus ROG Strix Z790-I won't power on

[Terydan]

I have a Strix Z790-I with Intel 13700K processor that I built a little over a year ago and has been working great. I disabled all overclocking functions in the bios several months ago when the microcode issue came up, and have upgraded to the newest bios as they were released except the most recent. I booted my machine the other day for some light work and then let it go to sleep after a couple hours with plans to come back to it, only to find the machine powered off later and would not boot. I began troubleshooting to the ultimate extent that everything was removed and placed on the bench leaving nothing but the motherboard, cooler, and power supply, and it still would not turn on. I get the leds on the network port when power is connected, but that is the only activity. I tried to power on via the designated pins on the mobo. Ultimately I RMA'd it to ASUS and just got it back with the fix supposedly being that the BIOS were messed up so they flashed the latest. Hooked it back up on the bench just to test and it seemed to have the same issue as before, but then suddenly booted. Got a "no bootable disk" message since I hadn't connected NVME yet. Figured all was good, reassembled PC and tried to boot. I got a momentary attempt at booting then powered off. Tried several times, clear CMOS button, etc. Sometimes it poweres on and off a few times before shutting off and staying off. I have pulled it all back out again with it sitting on my bench, just the mobo, cpu/cooler, and power supply. Tried 2 power supplies and no difference. Any ideas what is wrong, I don't think ASUS will RMA it again since they seem to think they fixed it.

[Jiaszzz_ROG]

Hello @Terydan 

Based on your description, you have already performed minimal hardware testing, including removing the chassis and installing only the CPU, CPU cooler, and PSU, as well as cross-testing with two different PSUs. May I ask if a single memory module was installed in the DIMM_A slot during the test and have you try clearing CMOS?
Aside from the LAN port indicator lights, are there no Q-LED indicators soiled when the system fails to boot?

Considering the timeline of your PC build and the CPU specifications, we recommend referring to the following articles:
July 2024 Update on Instability Reports on Intel Core 13th and 14th Gen Desktop Processors
[Intel] Sept 2024 (Update on Instability Reports on Intel Core 13th and 14th Gen Desktop Processors
In addition to verifying whether the CPU is correctly installed and ensuring there are no bent pins or loose or overly tight installations, we also suggest cross-testing with a different CPU to further isolate the issue.
Regarding repair details, as this involves personal information, I have DM you to confirm further. Kindly check it at your convenience.

Thank you.

[Terydan]

Tried a single RAM stick in slot A and also in slot B, tried a different stick as well, no change. QLED is on Strix Hive module connected via USB and there is no lights or anything from it or motherboard, other than aforementioned LAN status LED. The power supply is Corsair SF750 and makes a very audible click when it powers up, and I never get anything from it when trying to power up from motherboard. It's almost like the Power On signal never gets sent from motherboard to psu. Tried clearing CMOS per the instruction manual, no change. Unfortunately, I don't have another compatible CPU and I don't know anybody that I can borrow one.

[Jiaszzz_ROG]

Hello @Terydan 
We apologize for any inconvenience caused by the delayed response and appreciate the detailed information you provided through both comment and DM.
May I kindly confirm whether, after connecting the HIVE, any Q-LED indicators are solid during boot failures?
Based on your description of having cross-tested all hardware components except the CPU, and considering that the motherboard has been repaired and verified, we recommend evaluating the need to send the CPU for inspection or reaching out to your supplier for further guidance or assistance.

Thank you for your understanding.

[Terydan]

The Hive is connected but never illuminates any lights. The motherboard physically does not power on at any point. My understanding is that even with a faulty CPU the motherboard should at least power on. I do understand it may not boot if the CPU is faulty. But please understand that the motherboard never attempts to power on at all. At this point you are leading me to have to purchase a multi-hundred dollar part to diagnose the CPU aspect, but before I can do that I need confirmation that a faulty CPU would prevent the motherboard from attempting to power at all, because all the references I can find suggest that the motherboard should power on with a bad CPU so that it can annunciation via Q-LED or ther means that something is faulty.

[Jiaszzz_ROG]

Hello @Terydan 

Thank you for reaching out to us. We apologize for the delayed response due to a public holiday in our region and any inconvenience this may have caused.
Based on your description, if you have concerns about the motherboard, we recommend considering whether a repair service is necessary. Please contact your original reseller or the ASUS support team in your region to arrange further inspection and repair if needed.

Thank you.

[Terydan]

I have replaced the processor eith a brand new one and the issue remains. As you mentioned, I have performed all the other troubleshooting so this brings us back to the motherboard being at fault. I believe the board needs to be re-evaluated and that it was not properly verified before being returned. Please advise on next steps.