============================================= EDIT : I don't initially want the EFI bootscreen for this card - just want to get it booting into HS. ============================================= Bought a cheap, used FirePro v7900. 2 gb 4 x Display Port here in Japan today because it is a single PCIe slot and only one 6 pin for power = would be a useful adjunct for flashing other cards in Win7 ( 6 pin ). It's device ID is listed in Win7 GPUz as 1002 6704 and also the same in High Sierra's AMDLegacySupport.kext so I expected that using ACTIVE DP to DVI adapter that it would boot into High Sierra 10.13.6. Tried DVI to DVI. & DVDI to HDMI cables with the TWO active adapters I also bought. TDP is 150w. I tried BOTH ( 1) 2 x SATA to 6 pin &. (2) 1 x cMP onboard mini 6pin to 6 pin with no luck. It DOES boot into Win 7 but after installing the AMD Catalyst driver it is still showing as GENERIC GPU in GPUz. ==================================================== Does anyone know which equivalent 6xxxx AMD card the FirePro v7900 is based on ? eg : would flashing the Cayman 6970 or Cayman 6950 rom with this FirePro v7900's correct device ID 6704 get it booting in HS ? EDIT The reference HD 6970 has 2 x mDP. . . I would be happy with one mDP working ( no EFI ). Seeing that I've seen vids of other FirePros running in cMPs .. this one SHOULD run in HS too. Any advice, suggestions, ideas gratefully appreciated.