Yes, a PSU can be designed without any PCIe power connectors.
Yes, a PSU can be designed without any PCIe power connectors.
I've updated the motherboard and tested a reliable graphics card. The power supply is a brand new G6. The 4090 doesn't have a fan spin, but the lights work. The working 2070 I tried had fan spin, but it showed a black screen saying to connect all power cables to the card.
After reviewing both discussions, you should eliminate the PSU. That leaves all other options open.
I've always considered power supplies to be among the most dependable parts of a computer, which makes me puzzled if a brand-new PSU could be the issue. I'm planning to get a replacement.
I figured it out. I swapped the PCIe connector originally meant for the power supply into the graphics card. This worked for three out of four cables I tried. The damaged ends ended up fitting the PSU easily. Both the clips and plugs matched perfectly on both sides. I used an EVGA Supernova G6 power supply. After checking online, it seems this method won’t harm either device—just skip connecting the sense wire and ensure the GPU boots normally. No one else seems to have faced the same problem, since most PSUs are built to handle this.