Displayport won't display unless vga cable attached, HP 6300

[Norry77]

Here's what's going on; someone I know bought a refurb HP 6300 and asked me to help them hook everything up. I did. On boot the power light on the screen, hooked up with displayport, turned blue as though it was going to display something, then went on to say no signal. I thought, perhaps, it needed to be hooked up through the VGA to set displayport as default option, so I happened to have a screen, cable, etc. and tried. Well, that worked, got into bios, saw no option to chose which would be default. I decided to go ahead and launch into windows and just leave it alone since wouldn't need to get into bios often enough to be too worried. I had the displayport screen still hooked up along with the VGA, and windows came up, and the monitor connected to displayport came on, set up windows, got connected things seemed fine so I shut down. Disconnected VGA, rebooted. Acted the same, light turned blue for a second, then no signal and no display. I could hear the computer was booting and was confused. Reconnected the VGA after shutting down. Boot went fine. Both displays came up. Did the usual, update windows, update drivers, bios, unhook this, hook up that, try different cables, screens, etc. This went on for a while trying to get just the 1 screen on the displayport to display windows, but it would only come on while the VGA screen was connected. I got the bright idea to unhook the VGA from the screen, but leave the cable hooked up to the computer itself. It worked. With just a vga cable hooked up, the displayport screen came on and seemed to be fine. I honestly haven't ever come across this before and have no idea what could actually be wrong. Can I just leave a vga cable hooked up to the computer and leave it working, sure, but that's not normal, optimal, or correct under any circumstances I've encountered before so I'd like to find a real solution. Should I have them send the CPU back as bad? Is there anything I can do? Is that actually normal for that HP computer? I sure haven't found this same issue anywhere I've searched. Just leave it until later and have them upgrade to a video card which would enable me to select that as default display and the problem may well just go away from there. Still if there's something wrong causing this then what issues could be expected going forward?

Anyway, grateful for any help.

[The_Fossette]

@Norry77,

Welcome to the HP Support Community!

I assure you I will try my best to get this sorted.

In order that I may provide you with an accurate solution, I will need the product number for your computer.

Follow the steps in the below article to find the product details.

https://support.hp.com/us-en/document/c03754824

Look forward to hearing from you and you have a great day!

Take care.

Cheers!

[Norry77]

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