I recently had a PC built for me, and while everything powers on and the fans are spinning, I'm not getting any display output from the HDMI port. We checked the power cable on the motherboard and found it was loose, but aside from that, we can't seem to find any other issues. My boyfriend has already reseated the GPU and RAM, but we're kind of stuck here after a long day of troubleshooting.
4 Answers
Also, check your monitor's input settings. Sometimes it needs to be manually switched to the right input source.
Here are a few steps to consider:
1) Ensure that the GPU is properly powered and that you're plugging into it instead of the motherboard.
2) Does your motherboard have diagnostic LEDs? They can give you clues about what's happening during boot.
3) If your CPU supports integrated graphics, try booting without the GPU and see if you can access the BIOS.
First, make sure the HDMI or DisplayPort cable is connected to the graphics card, not just the motherboard. It's easy to overlook, especially if the cable is long or wrapped around other components.
Give it a couple of minutes to boot as well. When I first built my PC, it took a bit to display anything, probably due to the RAM initialization. I panicked initially!

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