Sajin
Try this...
 
#1 Download  and run it.
#2 Right click on the button that says "Show overclocking" and select "Multi Display Power Saver"
#3 Under the Target GPUs section check mark both GPUs.
#4 Check mark run multi display power saver at startup.
#5 Check mark activate full 3d by gpu usage and adjust the threshold to 30%.
#6 Close NVIDIA Inspector. 
#7 Reboot PC.
#8 Check to see if clocks are running at lower speeds. 

Just want to say thanks for the info; just got a EVGA 980 SC last week and after I added my second monitor my GPU was idling hotter than it should. This fixed it no problem; I didn't even need to reboot for it to take effect.

I might have to try this as my 3 monitor set up prevents the card from idling and boosting, but with two monitors it acts fine. I even RMA'd the card for this reason and decided to send back the replacement because it had coil whine.

I have a GTX 970 FYI

I think it's a refresh rate thing. If any monitor has a different refresh rate, then the GPU goes to full load. If you can sync the refresh rates, it's should downclock normally. I have three monitors all running 120hz and the GPU downclocks to 135mhz. The moment I connect a 60hz screen, it jumps up to 912mhz and stays there. 

Sorry to dig up and old thread but it has the information I was looking for. 
 
I just installed a second 980ti in a triple monitor setup. I was idling at 912mhz! I followed Sajin's directions and I am now idling at 405mhz. 
 
Is this still the best method to down clock an SLI Surround setup? I don't remember having this issue when I had 2x780 Classifieds. 
 
BTW, I was using driver 364.72 but upgraded to 368.39 and that didn't change anything. 

Yep, I think you are stuck with that. :)

I guess I will just use Nvidia Inspector then. I am amazed Nvidia hasn't come up with a solution to this problem. 

The high GPU usage is not normal and Nvida admitted there was an issue last fall, nearly a year ago. Some tech on line magazine discovered the issue, contacted Nvida, and Nvida confirmed the issue. I posted the link months ago but somehow theses facts seem to be forgotten.

Nvida promised a driver fix and one was released a month or two later, however it only seemed to help those with two monitors, not three monitor set-ups. It is not normal for the GPU To increase from 135 to over 960 plus by simply changing one of three monitors running at 120 to 144 while the computer is doing zero work.

It doesn't appear there is a fix, for whatever technical reason, but Nvida has been aware of the issue since last fall. There was an explanation of the issue but they may have gone as far as they can.

dc8flyer
The high GPU usage is not normal and Nvida admitted there was an issue last fall, nearly a year ago. Some tech on line magazine discovered the issue, contacted Nvida, and Nvida confirmed the issue. I posted the link months ago but somehow theses facts seem to be forgotten.

Nvida promised a driver fix and one was released a month or two later, however it only seemed to help those with two monitors, not three monitor set-ups. It is not normal for the GPU To increase from 135 to over 960 plus by simply changing one of three monitors running at 120 to 144 while the computer is doing zero work.

It doesn't appear there is a fix, for whatever technical reason, but Nvida has been aware of the issue since last fall. There was an explanation of the issue but they may have gone as far as they can.

This thread is a year and a 1/2 old. Good job .

Hey Stalnx20 something,

The most recent driver release attempted to address the high GPU usage again by enabling some function previously not enabled. I addressed that issue in my post yesterday and while discussing the most recent driver in that section, Sajn Linked this thread.

So Stalnx20, maybe you can go back find my most recent post on the most recent driver and offer some constructive input concerning the most recent driver release and Nvida's most recent attempt to address the still uncorrected high GPU usage.

I won't hold my breath for that.

I run my monitor on 144hz with GSYNC and it clocks my GPU at 135mhz idling. Sooooo, what now?