Running windows 7, 64-bit. Motherboard has an on-board radeon 4250, and I have a separate 6800 installed. I only have 1 monitor, connected to the 6800 (the monitor does have both DVI and VGA connectors, though the VGA is normally disconnected).
This morning windows updates were installed, requiring the usual reboot. AMD Vision Centre or whatever it's called prompted for an update, which has never caused any trouble prior to this morning. During the driver install, the warning comes up about the screen flickering or going blank, and then the display goes blank. It does not unblank (as it were). The monitor light does stay steady, so it does appear as though it recognizes that it's connected to something, it just does not display.
I tried to connect instead to the DVI on the onboard 4250, at which point the monitor gave me the "Cable not connected" alert. Connected the VGA cable to the onboard, and I did have a display, albeit 800x600 (as opposed to 1680x1050 I usually have).
In the Device Manager, both display adapters appear, the 6800 as "working normally" and the 4250 as "Windows has stopped this device because it has reported problems. (Code 43)." If I uninstall the drivers, etc, I get the 6800 DVI display back, and both adapters show as working normally in the Device Manager.
I tried running AMD's device-detector program, and it only gives me the option to download the 4250 driver package. If I do that, I get the same problem as described above. If I manually download/install the 68xx package, I get the same problem as described above.
I tried googling solutions, but didn't see anything of a similar enough nature in the results to warrant attempts at those solutions.
Anyone have any ideas or advice for this? I've contemplated disabling the onboard device and then installing the drivers, but I'm concerned that it will do the same thing, give me an apparently non-responsive display with no means of getting back to even the onboard.
Did you try to update your 6800 drivers through the Device Manager manually ?
When you download the driver package from AMD and execute it, it expands to C:\AMD\..... where C: is your system drive.
Open Device Manager and expand Display Adapter. Double-click 6800 adapter and click Driver tab. Click Update driver. Select Scan my computer for a better driver. Then show the path to the driver .inf file. It shoıld be in AMD\...\Packages\Driver\Display\...Make sure the subfolders is checked.
your suggestion did help actually, though not quite in the manner you had intended I suspect.
Updated the 6800 as you suggested manually, and it did exactly the same thing (dropped to the 4250 vga connection, etc). Downloaded and installed the 4250's drivers afterwards manually, and it looks like that solved the problem. Extremely annoying, but I appear to be good.