JohnC_21 is correct, if it doesn't show up on the Device Manager then the OS doesn't see it. In addition to the followup questions he asked:
- Does the PSU output at least 24A (which is 288W) on the +12V rail per mfg. spec? You will either have to open up the case and look (snap a shot with the cell phone) or look it up at the mfg. support page or in the PSU's manual. On the PSU it will look something like the image below.
- Is the card fully seated? I guess if you get some lower resolution signal it is.
- Did you remember to plug in both PCI-E 6-pin auxiliary power connectors? Are they fully seated. If the PSU is modular, are the cables fully seated into the PSU as well?
example PSU specs on side:
Note this "680W PSU" has most of its amps on the +5V rail, lol. It splits its +12V rail into three: +12V1, +12V2 and +12V3 rails. The main bus (24-pin and CPU aux. power 4 or 8 pin) are on the +12V1 rail, along with any expansion card's slots and the MB chips that require any 12V power. The other two rails are usable by the drives and other components needs. It also doesn't list at what temperature this output was measured.
Edited by Fascist Nation, 07 May 2016 - 06:59 PM.