I had this same issue when I first got setup.  I would have lockups where the computer is technically on but unresponsive.  It would take a physical shutdown to clear it up.  So I made an arduino resetter hooked to transistors which shorted the pins on the power/reset switch, then I wrote a GUI that was intended to run on a "monitor" machine that was not mining.  The GUI had buttons to reset/power down with an indicator that changed when the power was on/off.  Then I could just log into Teamviewer and do the physical reset.

By the time I got it all done I didn't need it anymore.  I got all my heat/overclock issues stabilized and it never needs shutting down.  Aside from one power outage my miners have been running 3-4 months solid.  I decided it was not worth the small amount of hashrate increase if I had to go reset the thing all the time. 

I run 5x Sapphire 5830's in one machine for around 1.5Gh/s.