I recently bought te 601 by accident by clicking on the wrong item and not realizing it until it showed up at my doorstep. The only difference that I originally thought I seen was that the front panel has input for mouse/usb/keyboard and etc. However, I just realized that the 601 doesn't have the switch to control the fan speed of the intake and the exhaust. Is this normal?? I ended up getting some Papst fans instead, but I'm still curious why they left this feature out of this case and if I am making a big mistake not sending this case base for the one I originally wanted.