Unable to get 8 monitors to work at same time with dual nvs 420's

dmavro

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Feb 11, 2010
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I recently purchased 2 nvidia quadro nvs 420 graphics cards. Ive only been able to get 7 displays to work at same time. Whenever i enable the 8th monitor one of the other 7 that r enabled gets disabled. In windows settings monitors 1 ,2, 3, 5, 6, 7, 8 are all active. When i activate monitor 4, monitor 3 is automatically disabled. However, i can get monitor 4 to duplicate monitor 3. But i cannot get them all enabled as extended displays which is what i need. I have 4 ASUS 24" monitors( all working- set as monitors1,3,5,7) , 2 dell 1908FP's( one working, one not working- monitors 4 and 8), 1 dell 1907FP( working- set as monitor 2) and 1 Dell E207WFP(working-set as monitor 6). I am using DVI connections for all monitors.

Anyone have any ideas?? Dont know if its something as simple as switching which ports displays are connected too. I tried that once but maybe i set up wrong way again. Or maybe resolutions for the displays..... I have the ASUS's set up as 1920x1080, the Dell E207WFP set up as 1680x1050 and the other the Dells set as 1280x1024.

System im running is intel core i7-930 with gigabyte GA-X58A-UD5 mobo, 6gb of ram.
 
Solution
This is a common problem with these quad display cards. Each card has two gpus each driving two monitors. So start with testing each card to see if all ports can be enabled at once. It is possible that one card may either be defective.

dmavro

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If troubleshooted it a little more. One of the cards is only letting 3 monitors work at once. I unplugged the quad DVI adapter from the other card and realized that whenever i enable monitor 4, monitor 3 shuts off automatically and vice versa.
 
This is a common problem with these quad display cards. Each card has two gpus each driving two monitors. So start with testing each card to see if all ports can be enabled at once. It is possible that one card may either be defective.
 
Solution

dmavro

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Originally i thought it was the graphics card, but now im thinking it has something to do with mobo. No matter which card i put in the pcie-x16 slot 1 of the mobo i still get same issue. I can only enable 3 monitors at a time in that pcie slot. Ive tried switching monitors and ive tried switching quad adapters and nothing changes.