SLI Causes Fullscreen Games To Have Extreme Lag And Stutter

[Maxarini]

I Installed another GTX 980 Super-clocked in my rig and ever since then whenever I play a game that has reasonably good graphics in full-screen mode, I get significantly less fps and an absolute ton of stutter making my games unplayable unless I go into windowed mode.

I tried turning off sli in the nvidia control panel and everything went back to normal.

How can I solve this issue? Why does this only happen if Full-screen mode?

THANK YOU IN ADVANCE!

If it helps I have an Asus ROG motherboard, and Intel 4790k CPU running windows 8.1.

 

[George Phillips]

This is a common problem for early 300 series drivers. First, try to download the latest driver and clean install the new driver. 2nd, check the PCI-E configuration for your cards. 4790K processor doesn't support two PCI-E 3.0 at 16 but only at x8 the most. If there are other adapters, one of your cards may be getting even less bandwidth than the first one.

 

[Tradesman1]

What PSU?

 

[Maxarini]

My PSU is the an EVGA supernova 1000g2 (http://www.amazon.com/gp/product/B00CGYCNG2?psc=1&redirect=true&ref_=oh_aui_search_detailpage)
1,000 watts is enough power for two 980's right?

I will try to uninstall and then re-install the latest driver. When I installed the graphics card I did not uninstall the driver though. Would that be causing this?

Also how do I "check the configuration for my cards"? I'm not quite sure what you mean by adapters but there are none that I know of.

Thanks guys!

 

[Maxarini]

So I did a clean install of the latest driver and everything seems to be working. Thanks a lot for your help. Now I can finally enjoy SLI.