New graphics card - lost 2 additional monitors

Had to replace old power supply and graphics card...both went smooth or so I thought...

Have 3 monitor set up which has worked fine for years...after installing new graphics card...zI can run monitor one by itself without issue...but when I connect monitor 2 or 3 I 'loose' all montors... nothing works...if I disconnect monitor 2 from the card..then monitor 1 works fine...reconnect 1 or 2 other monitors...then all blank screens !

Any thoughts on what's up with monitors 2 and 3 and the new card ?

Ummm----do you think it might help a little bit if we know what make/model graphics card you are talking about?

What are the resolutions of the monitors trying to be used?

They are both smaller monitors (Asus and Samsung)...resolution is considerably lower (I think) than the larger main monitor....since I have to turn off the system/box to switch/swap the monitors on/off to check the resolutions...I will post back tomorrow morning with the details...

The screen diagonals are about 18" on each smaller monitor and they are Samsung and Asus monitors...the main working monitor (Samsung) that is connected now is about 28-30 inches (diagonal) at 1600 x 900

This all started when I had to replace the power pack in the box...at the time it seemed the graphics card had also gone bad...but the card is back in the box now so that doesn't seem to be connected to the current problem.

Thanks so much for your efforts...will have info back to you via form posting in the morning...TiminAz

Try turning off Windows Fast Startup:

Turn On or Off Fast Startup in Windows 10

3 Digital signals at the same time can be tricky.

It can depend on what type of 3 screen setup is being attempted. Eyefinity always relied on 3 forms of connections for a true triple screen layout. DVI (VGA) , DVI or HDMI and Display Port. The use of the Display Port was crucial.
If you are running just Extended Desktops, there still might be an order process of installed screen displays and which to connect first.

1st connection,
I would get a DVI to VGA adapter and lead and run that from the DVI (VGA) port on the Geforce, straight to the PC connection of the Samsung 31" TV. This being the biggest screen, so i assume its in the middle. Restart machine and see if you get the TV to fire up on its own. Fingers crossed it will.
Now get into Windows and run the 31" TV at its native resolution, which should be something like 1366x768, maxing out the VGA leads display. Turn machine off.

2nd connection,
Now connect the 2nd DVI port to the Asus 21" and restart machine again. Asus 21 should be recognised as the 2nd screen now and hopefully comes on. Same as before, match the resolution height so its similar to the 31". So lets try 1280x768.

3rd connection,
Once Windows loaded up, I will assume you have 2 working screens so far, Sams 31 and Asus 21. Before you connect the 3rd screen, could there possibly be any Nvidia driver settings, that have to be enabled for a 3rd screen? Its worth having a good look through the driver settings here.
Connect up 3rd screen now and see if she comes on. 1280x768 again.

If you still cant get the 3rd screen to fire up. Well then I would install both Nvidia cards into the two PCI-e slots the motherboard has. Run the 31" off the GT740, and then the other 2 screens off the GT710. You might still have to run the VGA lead into 31" TV, no matter. At 1366x768 and 100% DPi she'll look nice !
Regarding the DPi settings too, make sure you let Win10 automatically adjust DPi scaling so all 3 screens dont get screwed up.

Hope this helps abit bud

Thanks guys...as always I appreciate all the guidance on this (and past issues) on this great forum. Got all three up and running properly again...not sure why or how I got them going but back in business again.

One of the three is actually a TV but can be used as a monitor (has been (with the other two) for a number of years)...I 'think' the main problem was I had to reset this particular TV/monitor to work as a monitor...not a TV ??

May or may not been the problem but all three are up an running fine now.

Thanks again to Pluginz and all that helped me struggle thru my re-setting up the displays

Appreciated it....TRinAz

Ah brilliant stuff, glad its working, stupid computers eh
Im pretty sure the bios and boot screens run quite a low resolution and can confuse digital connections on post screen. Sometimes the 2nd or 3rd screen doesnt actually wake up and turn on until you get to the login screen. Can be confusing thinking its not bloody working, when it is