windows hdr vs Linux hdr issue

I have 2 pc’s and on both I get this issue:
Hdr/tonemapping looks fine on both in windows.
But in Linux they have a huge over exposure.

My tonemapper settings:

Technique: AdaptiveReinhard 
grey: 0.4 
White: 2 
Adaption speed: 0.4 
texture size: square 512



I realize this is an old post but we just came across a very similar issue. Our version of the issue was represented as a darker screen in Linux than what we were seeing in Windows.

Our solution was to switch the windows machine to use Open GL which then matched our target machine running Linux. The development machine was initially using Direct X.