3rd Monitor Not working

Question

We have just moved offices and when it came to setting up one of our computers one of the monitors won't work.

The computer in question has windows 7 and a geforce 7300 LE and GT 430 graphics cards enabling 3 monitors. At the current situation 2 monitors work using the geforce 7300 LE but the third off the GT 430 won't.

I've updated and reinstalled the drivers which should work (I read I need the same driver for both) and that doesn't work. I've removed the GT 430 and blew off any dust I could see with one of those blowing devices.

I've tested the monitor itself and it's cable and that seems ok.

Windows 7 doesn't say any hardware problems and before the move it was fine - it also tells me all 3 monitors are there (Nvidia's software says the same)

Does anyone have any further ideas - all I can think of is remove the other graphics card and see if it will work of on it's own but that won't fix the problem.

On another note we also had a problem with an xp machine, (3 monitors again) this gets weirder - all the monitors were working and then one day one decided not to work - again, tried reinstalling drivers but no dice. Tried replacing the cable but nothing changed.

What could be the problem, and how can it be fixed?

Answer 1

So then the issue is not the monitor but the driver or configuration.

Have you tried uninstalling the drivers or deleting the video card from Device Manager and rebooting?

I've found issues with some Display Port connectors on multi-monitor setups in our office. If basic steps don't resolve the issue, deleting the graphics adapter and then rebooting tends to resolve the issue.

Note: Delete from Device Manager and reboot first. Don't uninstall the drivers unless you tried the previous step first. Basically you're telling windows to re-find the device and reconfigure it, which is usually enough, and made easier by leaving the drivers there for it to re-find. Removing the drivers adds a few layers of complexity and a few extra steps not worth doing unless necessary.

Answer 2

You've probably already done this, but make sure you're plugging the monitor into the right card, also make sure they plugged into the ones they were originally.

Answer 3

The answer was to remove the graphics card and replace with another looks like the computer just didn't like it. I tried moving cards around but in the end it just needed a different card.