To be of real use the update rate of the deformable mirror has to be
as
fast as the major components of scintillation are changing. In windy
conditions video frame rates of 30 or 60 times per second are none
too
fast. It takes a healthy computer to analyze each frame, compute the

motions for all of the actuators and set them in well under 1/60
second.

For a computer which has nothing else to do than read a CCD only one
computer would be needed. If it also has to keep a telescopes
altitude
and azimuth servos correct, run an autoguider, and still allow the
telescope operator to play video games it might take two.

the AO system for Gemini north uses a 400Mhz IBM Power PC processor.
just to give you a benchmark that is about as powerfull as a $150
Playstation 2. to handle every computer controlled operation (including
AO) an astronomer is going to use can be easily handled by a standard
PC of last year.