I play Deus Ex from time to time (finished it twice on PS3 so not really in a hurry to finish it on PC), but I've never run into any performance issues. In fact, I can pretty much max it out with Direct X11 and it's silky smooth. Have: 2.8 Dual Core, 4GB Gaming RAM and Geforce 550Ti, Windows 7 32Bit.
Have you tried any of these?
http://www.youtube.com/watch?v=ih9ztmBFYDw
http://forums.steampowered.com/forum....php?t=2567606
http://forums.steampowered.com/forum....php?t=2111377
