I have a similar issue, unfortunately I don't have a resolution.
My Radeon 6970 regularly seems to drop the connection to the monitors. The screens (3x Dell U2711) all go black for about 5 seconds. Then they come back... sometimes. No driver error or Window error. Only the hardware connection and disconnection sound.
Also, when they do come back:
- sometimes they have been reconfigured in a different pattern
- sometimes one or more of the monitors show no signal and the driver wont detect it
- sometimes one of the monitors will only display at 640*480 resolution and the driver can't adjust it up to the native resolution of 2560*1440.
It seems random as to when it happens and random as to the end result, it could be any one or a combination of the above three symptoms. It also happens on boot sometimes, e.g. right now, one of monitors has lost the connection, even after I rebooted and played with the cables it has made no difference.
If I play with the cables I can hear the Windows hardware device connection and disconnection sound, but I can never get the monitor to go back on.
I have the monitors connected via:
- 2* mini DisplayPort to DisplayPort adapters and 2* DisplayPort cables
- 1* dual link DVI cable from the port closest to the PCB (next to the DisplayPort ports).
I have tried different mini DisplayPort adapter cables and different DisplayPort cables; this didn't make any difference.
One of the DisplayPort adapters is the original that came with the Radeon, the other was purchased aftermarket; its a Accell B112B-001B UltraAV Mini DisplayPort/DisplayPort(female) Adapter. I have even tried another adapter from the local PC store, but this didn't make any difference either.
This has been the case through various versions of AMD Catalyst drivers. I'm currently using Catalyst v12.4.
PC Config:
- Win7 Ultimate x64
- Intel Core i7-950
- Gigabyte X58A-UD5
- Powercolor Radeon HD6970
- 4* OCZ Vertex 3 (RAID0)
- Seasonic Platinum 1000W SS-1000XP
- 3* Dell U2711 monitors
Anyone got any ideas? I was going to warranty my card and buy a GTX680 (being the first nVidia card to support three monitors), but that might not fix the problem if it's an issue with the adapters.