so the problem seems to be the video output, I don't see why you only can boot up with the onboard video card
You never boot up with the PCI card? not even once?
if you can, why don't you use the second output of the pci card connected to the tv and use the TV as extended desktop?
but actually it seems that the problem is the HDD cuz the error you're getting (boot has failed, sleeping forever)
try checking the HDD for bad sectors, and try using the SATA controller on AHCI fro the HDD
as you can see, there's a few different things that seems to be the problem, so try to isolate the main problem
another thing you can keep in mind, is it possible that you can stream Video/audio over the LAN?