Adding my latest test results with the with the GV-R785OC-2GD card with tests systems:
My own system, Gigabyte GA-Z68XP-UD4 rev 1.0 motherboard, Intel i5-2500K
processor:
* Boot loops occur randomly during boot with GV-R785OC-2GD card installed.
* Works alright with the older Sapphire 6850 GFX card
Friends older system, Asrock G41MH/USB3 R2.0 motherboard, Core2Duo processor:
* With GV-R785OC-2GD system produced graphical corruption on one boot out of ~20.
* System works alright with older Nvidia 580 card.
Loan system, Dell Aurora R4 with Intel mATX X79 motherboard, Intel i7-3939K
processor:
* System does not give picture from DVI connector with GV-R785OC-2GD card installed.
* System works fine with its own NVIDIA GeForce GTX 580 card installed.
So far the 7850 card now has now demonstrated out of normal behavior in three different systems. The Dell Aurora R4 system's no display being the strongest indicator that there is something wrong with the card. I will bring this up with the reseller where I got the 7850 card.