I shall describe the sequence of events as accurately as i can. 1) I havent used my mac pro for a couple of weeks 2) I switch it on 5 mins ago and it boots fine, I log in and launch safari from the dock. 3) Computer freezes, mouse doesn't move, complete unresponsive. 4) I push power button for a few seconds to force a shut down. 5) I power up. 6) boots fine, after surfing the web for a few mins, MP just reboots, no warning, screen just goes black and the fans and chime kick in. 7) doesn't get to log in screen, instead it reboots itself, fans and chimes kick in 8) doesn't like it, computer shuts down, front panel light blinking at 1/2 second intervals. What has happened? How do i fix this? How much is it going to cost?