Ubuntu(or maybe just Unity) lags whenever I minimize a window when there's no other opened window(others are minimized). I faced this problem after I install Ubuntu Tweak 0.7, Conky, OpenJDK 7, IcedTea 7 (if it does matter) There's no problem to: show and hide windows spread window open and close window I have set window minimize animation as Fade 220ms and Animation Time Step as 1 in CCSM but I honestly don't think this is the problem because when there's other opened window, everything is smooth. Ubuntu 12.04, Dell Inspiron 1525, Intel Core 2 Duo @2.00GHZ, 4GB RAM