Hello,
I have a 2 year old P7-1240 ... it is running Windows 7.
I just tried to install a EVGA GEFORCE GTX 750Ti card in it.
Card fits fine and HP Screen comes up .... but then black screen when Windows tries to boot.
Pulling the card and going back to onboard video works fine. I've done this numerous times.
From what I can see from talking with GeForce support, it appears to be either a BIOS issue or UEFI.
There does not seem to be a new version of the BIOS available under HP support.
Does the machine support UEFI?
When looking at Boot Order it would appear to, as it lists UEFI Boot sources.
Also in the BIOS there does not appear to be anyway to disable onboard video (as it is supposed to autodetect).
Card was new from the box so it is unlikely that it is defective (especially since it shows HP welcome/BIOS).
Help please, all ideas welcome!