Question HELP PLEASE!! - PC power cycling every 30 seconds, nothing new/changed in weeks

Aug 3, 2022
Hello all, before I get into this, just want to add that I have changed nothing new in my computer for about 3 weeks now, and that was two new sticks of RAM that were confirmed compatible with my mobo and I was gaming consistently with these new RAM sticks for those 3 weeks. I was last on my computer 3 days ago, everything was fine. I have not moved my PC or changed it in any other way before those RAM sticks for over a year.

so, as the title suggests, I tried to boot up my PC this morning and the lights/fans turn on, everything sounds normal, but the display on my monitor said it wasn't connected to anything and was going to standby mode. After about 20-30 seconds my PC shuts off for about 2 seconds then reboots, turning off again after about 28-30 seconds. I timed this over about 5 power cycles with my phone at almost an exact 28-30 seconds per cycle.

I've read alot of other posts about 2-5 second cycling, but not much on 30 second cycling. So I got online and did all the things. I unplugged the PC, plugged back in, didnt work. I made sure all connections were well seated on the mother board. I removed the GPU, still power cycled. Removed and tried individual RAM sticks as well as tried the old ram sticks I had before, and PC still power cycled. Removed CMOS battery for 30 minutes and held down power button on PC for 30 seconds during this time, still 30 second cycles. unplugged and reseated PSU power cables to the MOBO. made sure there was no carbon build up or whatever on RAM and GPU connectors. PC is not dirty by any means, not much dust at all from what I can see. My MOBO doesnt have lights for diagnosing issues and doesn't beep with removed memory.

I'm sort of at a loss, I'm not a very techy person and I'm pretty much at the end of my rope with this stuff, should I buy a new CMOS battery? (PC is only 1.5 years old - prebuilt). the PSU is about a year old. It may be the CPU? overheating perhaps? I just don't know how to check for that and where to look for thermal paste issues. Please don't reply with an answer stating to boot up and change something in setting or go into safe mode or whatever because as I said, my monitor is acting like its not plugged into anything, zero display. I do not have spare mobo's/GPU's, or PSU's to try. Anyone have any suggestions?

AMD Ryzen 7 3700X 3.6GHz
NVIDIA GeForce RTX 3070
Windows 11
liquid cooling system (not sure what kind)
ASRock B450 m/ac motherboard
Corsair Vengeance LPX 32GB RAM (2 x 16gb) 3200MHz DDR4 C16 DIMM

UPC#: 811842069755