http://bugs.winehq.org/show_bug.cgi?id=25723
Summary: PhysX causes major lag in Mirror's Edge. Product: Wine Version: 1.3.11 Platform: x86-64 OS/Version: Linux Status: UNCONFIRMED Severity: normal Priority: P2 Component: -unknown AssignedTo: wine-bugs@winehq.org ReportedBy: H3g3m0n@gmail.com
When the PhysX option is enabled (setting in the Video Options) in Mirror's Edge. When 'physics' things start to occur the game starts to get some major lag becoming unplayable.
Mirror's Edge doesn't make too much use of PhysX (I believe it was on of the first games with support for it), afaik it's mostly used for enabling shattering glass to create shards and maybe some bits of paper on the ground.
As such this only seems to happen at specific points in the game. For example Chapter 1 Flight->Check Point D. As you are running across the bridge, the helicopter starts to shoot the glass causing it to shatter.
If you continue on to the next area, at some point (when you go underground) it suddenly returns to normal speed (most likely it has unloaded the previous area).
With PhysX set to off, there is no lag but no glass shards.