And one more thing before I forget.
In Brian256's pwm circuit, if I wanted to add a capacitor to the circuit so that the fans are given full power at start-up(I believe its called power-on-reset), what would be the best place. I was thinking about placing it between Vcc and the MOSFET. I haven't had a chance to try it yet, so I'll ask now.
Thanks for all the input.