Nov 19, 2020
My components: https://uk.pcpartpicker.com/list/k7dqsh
Quick list:
RTX4070 (founders)
Corsair Dominator Platinum DDR5, 6000, CL30, 2x16GB
Corsair HX850 PSU
Various NVME + SSD drives
Corsair H100i LCD CPU Cooler

Hi Guys, please help!

Built the above PC, all fans, case LEDs, LEDs on components all light and spin up but the system outputs nothing to screen.

The motherboard post lights for CPU and DRAM are always lit (each of the 2 lights is orange).

Please tell me I’m missing something obvious or a compatibility issue I’m not aware of makes my parts useless – have been losing my mind troubleshooting.

I believe all parts to be compatible out of box. Potential exception of CPU due to BIOS version, but have tried with a 7600x which I know to be compatible and outcome is the same.

A hopefully exhaustive list of everything I’ve tried to far to get the system to boot.

  • Checked case cabling
  • Checked all connections
  • Completely taken apart and rebuilt
  • Checked mobo pins are not damaged, CPU correctly seated
  • Check RAM slots and correctly seated
  • Check PCIE/card for damage and made sure seated
  • Bought a second (identical) motherboard, same result
  • Bought a second (identical) CPU, same result
  • Bought a 7600x CPU (in case bios needed update for the 7800x3d) and tried to boot
  • built on mobo outside of case
  • tried booting with no GPU (using AMD iGPU)
  • tried booting with a substituted gtx980
  • tried RAM in each of the dual channels, swapped the stick and tried again, tried a single stick in each channel, then repeated with the other
  • tried to boot with no storage drives
  • tried to power on with only cpu, mobo and psu connected
  • I intend to use a riser cable, but have tested with multiple, as well as with no riser (GPU directly in pcie slot on motherboard)
  • Reset mobo using onboard control
  • Removed mobo battery to clear
  • Made sure screen and HDMI/DP cables are working (used multiple)
  • …probably a few more basic ideas

Appreciate any suggestions… even if just to tell me the build was always doomed, at this point that would be wonderful news! I am losing my mind!