I've built a new pc with the following specs:
 
Platform:
Windows 7 (build 7601, Service Pack 1) 64bit
CPU model:
Intel(R) Core(TM) i7-5820K CPU @ 3.30GHz (3298MHz) x6
GPU model:
NVIDIA GeForce GTX 750 Ti 10.18.13.5330 (2048MB) x1
Nvidia driver version: 347.25/353.30
32 GB G.Skill Memory 4x8GB 
Asus Sabertooth X99 motherboard
Dual display, using both DVI and HDMI connections at the board, HDMI at the monitors
 
Having installed the driver that came with the GTX 750 Ti, which is 347.25, the computer will not wake up after having gone to sleep.  I've removed all drivers, except the video driver (3D, HD audio, etc.), and see no change.  I removed the Nvidia driver, and all other components and when it goes to sleep, it will wake up fine, but only single display works without driver.  I reinstalled the full complement of drivers and software, and see the same result, no resume from sleep.
 
I replaced the GTX 750i, with an older Zotac GT 730 out of another computer, and using the same drivers, the computer will go to sleep and will resume from sleep without issues.  I also replaced the video card with a PNY Geforce 550 Ti, and get the same results, no resume after sleep with either version 347.25, or 353.30.  I used an older XFX Radeon R5 220, and it has no issues with it's own ATI drivers going to sleep and resuming.
 
I also updated to the latest drivers, version 353.30, and get the same results, whether using only the driver, or having installed all of the additional component drivers (3D, HD audio, etc.).  
 
I've disabled the HD Audio Controller that corresponds to the same location on the PCI bus (PCI bus 1, device 0, function 0), to eliminate any possible IRQ conflicts.
 
I could continue to back rev the drivers to see if I can find a driver that might work, but does anyone have any ideas that would help in troubleshooting this issue?  The only difference that I can find thus far is the Nvidia video driver being installed that is preventing the computer from resuming after going to sleep.  The only option I have at the moment is to not let it go to sleep, or remove the driver, which are really not viable options.

tbadger
I've built a new pc with the following specs:
 
Platform:
Windows 7 (build 7601, Service Pack 1) 64bit
CPU model:
Intel(R) Core(TM) i7-5820K CPU @ 3.30GHz (3298MHz) x6
GPU model:
NVIDIA GeForce GTX 750 Ti 10.18.13.5330 (2048MB) x1
Nvidia driver version: 347.25/353.30
32 GB G.Skill Memory 4x8GB 
Asus Sabertooth X99 motherboard
Dual display, using both DVI and HDMI connections at the board, HDMI at the monitors
 
Having installed the driver that came with the GTX 750 Ti, which is 347.25, the computer will not wake up after having gone to sleep.  I've removed all drivers, except the video driver (3D, HD audio, etc.), and see no change.  I removed the Nvidia driver, and all other components and when it goes to sleep, it will wake up fine, but only single display works without driver.  I reinstalled the full complement of drivers and software, and see the same result, no resume from sleep.
 
I replaced the GTX 750i, with an older Zotac GT 730 out of another computer, and using the same drivers, the computer will go to sleep and will resume from sleep without issues.  I also replaced the video card with a PNY Geforce 550 Ti, and get the same results, no resume after sleep with either version 347.25, or 353.30.  I used an older XFX Radeon R5 220, and it has no issues with it's own ATI drivers going to sleep and resuming.
 
I also updated to the latest drivers, version 353.30, and get the same results, whether using only the driver, or having installed all of the additional component drivers (3D, HD audio, etc.).  
 
I've disabled the HD Audio Controller that corresponds to the same location on the PCI bus (PCI bus 1, device 0, function 0), to eliminate any possible IRQ conflicts.
 
I could continue to back rev the drivers to see if I can find a driver that might work, but does anyone have any ideas that would help in troubleshooting this issue?  The only difference that I can find thus far is the Nvidia video driver being installed that is preventing the computer from resuming after going to sleep.  The only option I have at the moment is to not let it go to sleep, or remove the driver, which are really not viable options.

Have you updated the BIOS on your mother board? Are you using the UEFI BIOS or legacy BIOS options. Is fast boot enabled or disabled? Which sleep state are you trying to use, S3? Have you tried Hibernate instead of sleep?

Have updated the driver to 353.38, and there is no change in how it is behaving.  Still no resume after going to sleep.  Will try hibernate to see if it does wake up from that.
 
I would note that I'm using USB keyboard and mouse - which seems to be norm these days.  The keyboard would appear unresponsive, that is pressing NUM LOCK would normally toggle the NUM LOCK state - don't know if I should expect any response from pressing NUM LOCK when in sleep state, other than waking up the computer.