Combine 2 video cards to drive 3 cloned monitors

[williefank]

Hello,

Subject: Combining two NVIDIA video cards to drive three monitors in cloned mode (each 1080p monitor is in a separate room). NVIDIA universal driver version 301.42, EVGA X58 Motherboard (two PCI-E slots), Windows XT Professional.

If I understand the forum discussions correctly, it's possible to combine two different video cards (non-SLI configuration) to drive three cloned or mirrored monitors. But when I combine a GTX 560 LE + a GeForce 9500 GT, and select cloning mode in NVIDIA Control Panel, the monitors do not clone, but display in extended mode ('horizontal desktop' or 'horizontal span'). The screens divide, with two monitors displaying the right side of the extended desktop, while a third monitor displays the left side of the extended desktop.

I need the same output to all three monitors.

 

[williefank]

Someone (not from this forum) recently suggested I use a VGA splitter.

Using a VGA splitter (off single video card) was my first solution to driving three cloned monitors. Perhaps because my runs are so long (distributed to three separate rooms) I experienced inconsistent results. This arrangement would work fine for a day or two, then one of my VGA monitors would go blank or would display the “Out of range” error message. I found that the only reliable way to use this splitter topology was to select a combination of two monitors from the NVIDIA Control Panel. In other words, I could use a DVI + VGA combo, but not all three DVI + VGA + VGA. It may seem a minor inconvenience to select a combination in the Control Panel each time you want to use a particular monitor combination, but it gets old fast.

 

[williefank]

Someone (not from this forum) recently suggested I use a VGA splitter.

Using a VGA splitter (off single video card) was my first solution to driving three cloned monitors. Perhaps because my runs are so long (distributed to three separate rooms) I experienced inconsistent results. This arrangement would work fine for a day or two, then one of my VGA monitors would go blank or would display the “Out of range” error message. I found that the only reliable way to use this splitter topology was to select a combination of two monitors from the NVIDIA Control Panel. In other words, I could use a DVI + VGA combo, but not all three DVI + VGA + VGA. It may seem a minor inconvenience to select a combination in the Control Panel each time you want to use a particular monitor combination, but it gets old fast.

This from NVIDIA Customer Care (11-26-2012):

"The option of having the displays in clone mode is only available when the displays are connected to the same GPU, while using 3 displays only 2 displays can be used in clone mode by connecting them to one card and the 3rd display would be in extended mode as it would be connected to a different GPU different graphics card.

"Also the GeForce GTX 560 LE graphics card is designed to support 2 displays simultaneously it would not be compatible with 3 displays setup."