Hey, i'm on freebsd 6.2 / xorg 7.2 / latest beryl with xfce4.
and my display likes to freeze, i've noted this problem tends to occer when opera spawns another window, although not always. i've read other solutions, one of which was a moddification to dwords in sysctrl (adding "PerfLevelSrc=0x2222" to it). that appeared to work, but obviously didn't..
Oh, and my card is a Geforce FX5900XT.