I have the same problem.
From what AMD replied so far (AMD_Robert on reddit to be more specific) custom cards can only support DVI-Digital, the 480 doesn't have a RAMDAC (RAMDAC is a chip that reads the GPU RAM, and convert the Digital contents to Analog).
Maybe he is wrong, and the 480 DOES have a RAMDAC or supports RAMDAC by the custom card makers... But I won't hold my breath, if you want to buy a new GPU "now", the 480 won't work.
I asked in another question, if I can buy a 480 anyway, and use older GPUs to output the analog data using their RAMDAC, I am waiting for a reply for that... But the answer is probably "no".
Reference cards don't come with DVI, The Custom cards will. Sapphires new Nitro shows a DVI connector.
so does the new ASUS STRIX:
OP was asking about DVI-I and DVI-A.
The cards will come with DVI-D
This doesn't fixes his problem (or mine).