Enabling desktop effects using the fglrx driver causes a performance issue when maximizing and minimizing windows (a delay of 1 to 3 seconds).
I have a Thinkpad T400 with a Radeon HD 3400, and I’m using OpenSuse 64bit. I also have the same problem under Ubuntu 32 bit:
There are some patches on the Ubuntu bugreport that fixes the problem for me and others. I can also say that the patches make the system notably faster. I hope that the OpenSuse community can help solving this problem, either modifying Xorg or putting some pressure on AMD/ATI to fix the driver.