While we have downloaded and played the game with the new 13GB patch installed, we have not gotten as far as the crew over at Eurogamer has in evaluating the performance of the new patch and what this massive 13GB update actually does.
According to the findings by Eurogamer, in their pay testing the performance impact of the new patch is questionable with frame-rates dipping to as low as 22fps when the engine is under heavy load when alpha effects and a large number of enemies are on the screen. In the first three levels they found no real performance impact that would lead one to believe that the engine has undergone a serious overhaul to enhance the game play performance.
In the end, some might be disappointed in what the 13GB delivers because it would appear that while some tweaks and fixes have been made, the overall rendering engine still can’t always keep the frame-rate above 30fps. It does apparently lay the necessary ground work for the upcoming DLC, which looks to be the primary mission of this 13GB update.
Read more here.