ShadowPlay PC Game Capture Software | GeForce | GeForce
... tried capture fight in RES and it worked rly good.
Tried it on Crossfire and it's a really nice tool. Ex. there's a video buffer (set amount of minutes to buffer) and then press ALT + F10 to save the video 
Turn on "Allow desktop capture" to record in Crossfire 
System Requirements System Requirements for NVIDIA GeForce Experience | GeForce | GeForce : GeForce GTX class GPUs 900, 700, 600, 900M, 800M, 700M, select 600M Series
Download from ShadowPlay PC Game Capture Software | GeForce | GeForce
(Some) Shortcut Keys:
Alt+F10 Save last XX minutes recorded
Alt+F9 Toggle manual recording on/off and save
Alt+F12 Toggle FPS counter on/off
And some attached pictures:
