my only concern would be the current draw on the Vcc for the CPU PWN lead.....if you wanted to get really hands on, you could run the actual run lead for all of them off the cpu fan header, but i would be wary of actually powering 4 fans off 1 lead.....if the power were just running straight off the PSU you'd be fine, and you could tie the PWM lines all together on the mobo header
the fans are rated at 2.16 watts at 12 volts each the mobo manual reads total of 84watts max at 12 volts. Meaning ill be running 25ish watts total off 2 leads.