Several weeks ago I built a new computer using an ATI 4850 graphics card. I had it set up for dual monitor and from the start there were no problems making it work. It is set up for extended screen.
Yesterday a hard drive problem forced me to format and reinstall Windows XP, along with all the various drivers for the mother board and graphics card. Since then I have been fighting to get the dual monitor configuration working again with no success.
Both monitors do work and display the same information during system boot or when I'm in the BIOS. But as soon as Windows XP starts up the second monitor screen goes black. It is still getting a signal as the light in the power button is still green. I can move the mouse toward that screen and it doesn't stop at the edge of the main monitor, so I presume that it is working, but the display is just black.
Using the Catalyst control panel I can see that both monitors are recognized by their model number. When I click on the Identity button a large 1 appears on the main monitor as it should. I've double checked the resolution setting for the second monitor and everything looks correct. I'm just not finding the cause.
Can anyone offer any other ideas for tracking down the problem??
I hate to ask the obvious, but is the second monitor grayed out in CCC? If it is, you clicked on it, and extend desktop to this monitor?? Sorry to ask the obvious, but I can't think of anything else that would cause that. I've had 1 4850 with 2 monitors, 2 4850s with 4 monitors and now a 4870x2 and 4870 with 4 monitors, and haven't had any problems getting them to work unless it's a hardware issue (which it doesn't seem like since the port is obviously working before you get into windows and worked before the format) What does it do when you choose to extend desktop to this monitor in CCC???
Hi Richard - Thanks for your reply. First, I'm not familiar with the terminology, so please explain CCC. It is very strange that this just won't work. I've gone through all the same steps in Catalyst that I did in the original setup when it did work. In Catalyst Basic view the steps are straight forward and I did click on Extend Desktop, followed by selecting which monitor is the main and verifying the resolution, etc. In the advanced dialog I've tried everything presented. The software locates and identifies the monitor by its model number, so I know it is seeing it out there. When I click on Identity the number 1 pops up on the main monitor, and I suspect a big 2 is on the second monitor if I could just see it.
One interesting point. During all my messing around with settings I got it into a position of setting the second monitor as the main and suddenly I had both monitors working. All the desktop icons were on the second (now the main) monitor. It was just reversed from the way I need it. But when I switched things back then the old problem came back and the second monitor would not display anything.
I am even thinking about just swaping th DVI cables at the 4850 to see if that makes a difference, although it shouldn't.
Did you get this solved? I'm having the EXACT same problem! XP x64 Edition, nVidia GeForce 7600 GS card and two monitors. It only started happening recently - the second monitor just goes completely black but it's definitely still on and not sleeping as the light is green and the buttons on the front bring up the display menu options as expected - it's as if the OS is just outputting a plain black screen.
Sometimes the problem fixes itself after a while, sometimes it doesn't. I updated the nVidia drivers and the problem still remains.
I'd like to point out that the monitor on my left is recognised as number 2 and the right is number 1 (opposite to what I'd like but the desktop is still drawn on the left hand monitor and the mouse moves linearly from left to right across both monitors).
Chris - No, sorry but I gave up on it and moved on. I do a lot of video and image editing so the dual monitor was a convenience but not a necessity. I didn't have time to continue messing with it. Hope you find the problem.