[SOLVED] HP PC won't boot when a GPU is installed?

[pkim1230]

I have a tested and working RX460 that I want to add to my HP Pavilion Slimline S5780T desktop computer.

Here are some photos:

https://imgur.com/a/XFtC2Vj

View: https://imgur.com/a/XFtC2Vj



When I add the GPU and plug in the HDMI, and turn on the power, the fans start spinning, and the GPU fans spin too, but the monitor doesn't receive any signal and stays black.
I tried plugging in DVI cable instead and that doesn't work either.
I take the GPU out and plug in the HDMI to the integrated gpu slot and it boots up just fine.
I plug the GPU in another computer and it boots fine.
I have enough power in my PSU because it's taken from a working computer.
I think the motherboard isn't supporting the RX460. It's a GPU that doesn't require any 4-pin or 6-pin power from the PSU.
I updated the BIOS but it didn't help.
The computer just won't boot up when I plug in the RX460.
I went into device manager and disabled the integrated gpu, and shut down the computer and plugged in the RX460, and it didn't do anything. Black screen.
What's wrong here? Is my motherboard simply not compatible with the RX460? How can I confirm this?

PC Spec:
Core i5-2300 2.8Ghz
6gb RAM
BIOS: CHI_711.bin v7.11
Mobo: IPISB-CH Rev 1.04
PSU: PC Power and Cooling S61EPS 610W

 

[alceryes]

It looks like the RX 460 requires a UEFI BIOS. That motherboard only supports legacy (non-UEFI) BIOS.
That GPU is incompatible with that HP.

 

[pkim1230]

It looks like the RX 460 requires a UEFI BIOS. That motherboard only supports legacy (non-UEFI) BIOS.
That GPU is not incompatible with that HP.

Thank you. That seems right. I googled and got other people confirming this is the source of the problem.
What micro atx Motherboard would support both my i5-2300 cpu, ddr3 memory, and rx460, and also have wifi built into the mobo? Something that fits the budget would be enough.