is a self-described "Anti-Cheat software system" which scans for "known cheats, game hacks, and exploits similar to the way Anti-Virus software would scan a computer looking for a virus." Unfortunately, PunkBuster's default method of stealth memory "scanning" can freeze the system up when it runs into PowerStrip on an ATI Radeon, making online gameplay impossible with PunkBuster enabled servers for popular games like Quake3 Arena and Return to Castle Wolfenstein.
There is nothing you can change in PowerStrip to fix PunkBuster freezing, but changing PunkBuster's memory scanning mode will usually fix the problem - from the PunkBuster FAQ
PunkBuster "pushes" hardware and the Windows Operating System more than most software and uses functions in the Windows API (low level functions) that aren't used by most other programs. As such, there are a few cases where using PB can actually expose [sic] flaky hardware or other situations that don't cause problems for other software. Here are a few things that have helped other users make these problems get better or go away completely...:
From the game's main screen, press the tilde key (the ~ key) to bring down the console and enter the following line (without the quotes): "/pb_system 1".