Just bought a new Dell Workstation with an Nvidia Quadro NVS 420 card to support four monitors. I updated all drivers and windows and my system will only allow 3 monitors to work at one time. I only allows me to duplicate one of the monitors to the 4th monitor. Am I missing something or could it be a bad card. I tried a new monitor also but still the same problem. My connection is a 4 cable dongle to the card. I thought this was plug and play but apparently not.
Same problem here. I saw a statement elsewhere with no citation that the 4th display won't work with Windows 7 x64.
After I updated the drivers, if I try to enable the 4th monitor under the nVidia application, it gave me a balloon that says that the GPU only supports 1 monitor, and the system needs to be rebooted to enable the second one. A reboot didn't change anything.
Dell Support said it was an issue, but couldn't find any solution that said it was for Win7. He gave me the solution indicated for Vista and XP:
download the latest driver from nVidia, disconnect from the network, uninstall the driver, reboot and do not let Windows try to install the driver. Then, install the driver you previously downloaded.
Once I did that and rebooted, I was again back to three displays. But once I went into the nVidia control panel, it let me enable the 4th display.