STA driver in Ubuntu

I've got new 500G HDD for my Dell M1330 and reinstalled Ubuntu. After installation I experienced several freezes -- notebook blinked with caps and scroll lock leds and didn't respond to any keys but power off. Every time this happened while wireless was actively used. As I discovered, the source of the problem was STA driver for WiFi card. After I installed b43-fwcutter, removed STA, and switched to b43 open-source driver the problem went away.