Batman Arkham Knight is like a font of bad news at this point. The most recent information to appear about the game is that the PC version will not see Multi-GPU support as the developers have found it to be impractical to implement.
One of the developers going by the name wb.elder.pliny on the Steam Community chimed in during a discussion about SLI support for Arkham Knight. Apparently, the company had been working on trying to implement the feature in the bug-riddled game. However, it turns out that the graphical improvement came with too many risks of adding new problems to the game, and the feature was subsequently dropped.
On the bright side, the developer took time to inform the game community about the status of the game; even if it happens to be more bad news. At this point, it looks like there is little point to buying Arkham Knight on the PC. The console version has been running smoothly since launch, while the title has experience numerous issues running on computers.
[Source: Steam Community]