I've recently got Thief (2014 version, on Steam) and I got a pc that can run 64bit executables and use the AMD Mantle technology but if I try to start the game without the 32bit mode I just get a black screen for few seconds and then it quit to desktop without any visible error or problem.
Any of you had this error and managed to use the 64bit version with Mantle enabled?
My graphic card is a HD 7900, according to the specifics I should be able to run Mantle just fine.
Thank you to all in advance!
Best Answer
Some people have the same problem, but here is the solution. First, if you have more than 1 GPU, it's normal : Thief does not support (as of March 2014) multi-GPU. Maybe there was an update since then.
Of course, you have to check if you're using the latest drivers, and also if you uninstalled the previous one, to be sure they're not conflicting.
A user on a Steam community thread also said this :
Here is the source : Mantle not working