The game ready drivers for SWBF have destroyed my frame rate in BF4. I was at a constant 135fps @1440p with the last set, and now it's just making 100fps. I suspect they gone broke SLI again
Edit: Ah fixed it! It's not SLI, it's GSYNC. Nvidia have enabled vertical sync by default in the global driver options. This strangles GSYNC. Switch it off and your good to go with GSYNC.
If you disable vsync (in the nVidia control panel) with G-SYNC enabled it works differently now - On is old style G-SYNC behaviour, Off actually disables G-SYNC (so you get tearing) if you are able to render faster than the monitor refresh rate.
Its possible something is broken with the latest drivers - I didn't try changing the vsync option but with G-SYNC on and vsync on I was getting drops to 70fps (usually holds 120) and flicker on the display - going back to a slightly older driver and it works fine with the vsync option.