Question PC not starting following upgrade

Nov 28, 2021
Hi all,

I've spent the day upgrading my PC and now it won't start. I installed several new parts listed below in a new case with several existing parts carried over from my previous setup. Since I'm using a i7-11700K with a Z490-H I ran a BIOS flashback on a USB to update to the latest BIOS version.

Following the BIOS flashback which ran successfully I started the PC, all fans and lights on the system were working and the monitor was displaying two lines of text (can't remember what they said but I think boot or firmware were mentioned). After around a minute it then restarted 3 or 4 times displaying the same lines of text then turned off. The power button now does nothing however the motherboard is lit up when the PSU is turned on. I've attempted the following to fix it:
  • Checked that all cables were plugged in correctly (the RAM were originally in the wrong spots and the graphics card power cable was not connected)
  • Cleared the CMOS on the motherboard
  • Disconnected and reconnected all cables on the motherboard, water cooling and power supply
  • Attempted to power on by connecting the two pins directly on the motherboard rather then the switch on the case
  • PSU was tested using the paper clip method and the fan worked fine.
I don't have a motherboard speaker to test for POST beeps.

New components:
  • ROX STRIX Z490-H ATX motherboard
  • Intel i7-11700K 3.6GHz
  • Corsair 32GB (2x16GB) Vengeance RGB Pro 3600MHz DDR4
  • Corsair 275R Airflow case
Existing components carried over
  • Gigabyte GTX1070
  • Corsair H100i v2 water cooling
  • Corsair CS650M power supply
  • Two SDD and two HDD
I'm at a lost on what to do, I've searched around for suggestions online to no avail.