Nvidia is offering an amazing value for PC gamers: purchase either the GeForce GTX 970 or GTX 980 and you'll receive both Batman: Arkham Knight and The Witcher 3: Wild Hunt for free for a limited time:

Batman Arkham Knight

For those already in the marker for a gaming PC GPU, this is quite the generous offer. However, be aware that Batman: Arkham Knight is only available when you purchase a GTX 970 or 980, while The Witcher 3: Wild Hunt is available for a purchased GTX 960, 970 or 980.