RX 460 not working?

[Luddwi]

So, about a month ago, I bought a used HP P6 Pavilion (2185-ea) in order to upgrade from a laptop, by means of a new graphics card. However, after many attempts to fix the numerous errors, I have decided to see if anyone can offer any solutions to the issue.
Specs:
CPU:Intel i5-2320 @3GHz
4GB DDR3 RAM
GPU: GIGABYTE Radeon RX 460 2GB OC
Mobo: Cupertino 2 (see HP's specs)
PSU: 300W supplied with the PC
HDD: 300GB, 1TB
OS: Windows 10 64 Pro, Windows 7 64 Home (respectively)

Already tried:
Booting from the card = No output and mouse and keyboard are not supplied with power
Altering BIOS settings = No change, apart from a beep code indicating CPU issues. However, the PC runs just fine off of the integrated graphics​, and a check of the CPU seating showed no signs of problems, and the beeping stopped. Also the BIOS is limited (AMI) and provides little useful information
Removing and replacing CMOS battery = no change

The card definitely works, as the fans turn on, so power must be supplied. The integrated drivers were disabled before installing the graphics card. The card was tested on both OS's, and with two monitors, both worked with integrated, but neither with the graphics card.

I am at a loss with what to do, so any help would be greatly appreciated, as I am very frustrated with my lack of progress and results from the cost of the card.

 

[elbert]

The bare minimum for the rx460 is a 350w. You need a new PSU. This PSU will work with your ATX case and ATX motherboard power 20+4 connector.
PCPartPicker part list / Price breakdown by merchant

Power Supply: Antec - EarthWatts Green 380W 80+ Bronze Certified ATX Power Supply ($40.49 @ SuperBiiz)
Total: $40.49
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-05-18 18:52 EDT-0400

 

[Bill_Gits]

Hello Luddwi,

i have the same mobo and i can confirm that the problem actually is from the motherboard itself (because it's an OEM motherboard from HP), it hasn't got any BIOS updates since 2012 so that's why it's not able to boot with your new graphics card...however you have two options:
1- Easy way: there's a glitch in this motherboard which allows you to use your new GPU (but it's kinda makes your PC boot time longer) i saw that in this video:
https://www.youtube.com/watch?v=fkBTSlBW2oc (the guy in this video claims that it has to be tried in your own risk but im not sure about that since this method still works with him)
EDIT: recenly i bought an RX 460 2 GB and it didn't work with this motherboard no matter what (No signal) , so i think that a new motherboard is the only solution available (with an empty case) if you want to use this card, it's like rebuilding the entire PC from scratch but with another motherboard.
2- Hard way: buy a NEW non-OEM motherboard (like Gigabyte,ASUS,MSI,ASRock...etc) that is compatiable with your system (Socket 1155),along with a thermal paste and another case, even if you have an old one (because HP cases are limited to thier motherboards only just like the one you've mentioned,so you can't install any motherboard other that the ones from HP) just make sure it will fit the motherboard since both have diffrent sizes (ATX,Micro ATX...ect),and yes this requires you to rebuilt your entire PC from scratch (i have a lot to mention but that will make the comment too lenghty to read, to make it short you can use google to find tips about them)

Sorry fo bad english.
Regards,
Bill