I have an ECS GEFORCE 6100SM-M Socket AM2 board and I installed a Sapphire ATI Radeon X1050 PCI-express card to be able to use DVI. I get a really annoying problem where if I turn off my monitor manually while I'm in Windows and turn it back on again, I lose the video signal until I either wait until the display shutoff timer goes on and then resume it or put the computer on stand-by and resume.
 
I also noticed that this does not happen at all when I have generic Windows video drivers installed in place of the ATI drivers, however I get a really low resolution.
 
I have tried getting a better power supply thinking it was a power issue, but it did not help. I also have all the latest drivers and BIOS. People have suggested that it's a S3 resume to VGA problem, but I think the latest BIOS fixes it so I don't think that's it. Also I have onboard video disabled through the BIOS.
 
I think the PCI-express slot can only run at 8x instead of 16x... I don't know what that means but could that be the problem if my card is just "16x" and not "8x/16x" --if that even exists ?
 
Does anyone else have this problem and how did you fix it?

Or at least can someone tell me if they have this board paired with a PCI-Express video card using a DVI output that does NOT have this problem and which one?

This may just be a power management issue.  go into power options and disable standby mode, tell it not to turn off the monitor, and disable hibernation.  
 
Other thought is its a monitor issue.  The monitor may be cutting the signal or something along those lines.  To ensure its not the monitor plug in a crt or different monitor to test for the same issue.