I just recently started to build a new computer (my first time). I took my GPU/CPU from my old system and put it into the new. I ran into the problem that the system was not displaying anything and the CPU Debug Light was flashing. After looking into it I realized the problem was I didn't plug in the 4+4 in CPU_PWR2. I then rebooted the system and tried for a post again. It still doesn't display or post but now the CPU and DRAM lights flash. I tried going bare bones but the same problem occurred. I font have another system anymore to test parts.
CPU - Intel i7 8700 8th Gen
GPU- 1660 Super
PSU- Cooler master 650v2 Gold
RAM- Corsair Vengeance LPX 3600
MOBO- MSI Z390 Edge AC
CASE- NZXT H510i
AIO- Cooler Master not sure
and I have a HDD and a 1tb nvme
CPU - Intel i7 8700 8th Gen
GPU- 1660 Super
PSU- Cooler master 650v2 Gold
RAM- Corsair Vengeance LPX 3600
MOBO- MSI Z390 Edge AC
CASE- NZXT H510i
AIO- Cooler Master not sure
and I have a HDD and a 1tb nvme