I am having "compatability" issues with my new hardware. I have recently purchased an asus r9 270x 4g and a corsair cs550m. I am upgrading from my stock radeon 7450 in my hp h8 1234. I have tested the graphics card in another machine and it works fine. The psu should be sufficient but is it compatable?
I have seen at least three threads here lately about HP desktops not supporting certain, high end video cards. I would search your model HP and that card and make sure at least someone has been able to make it work. The mere fact there is a pcie 16x slot does not guarantee a card will work on the limited BIOS/Motherboards of branded PCs.