 the iso page does mention 'xorg' but presume that is for not being able to see things on screen before hitting the login screen. :
 could be xorg, could be the drivers (re @philipz: if someone is having problems with their display randomly going blank, what should this be filed against? linux?)
 so i guess no way to find out for certain without filing it against linux and bug triage changing it as needed. thanks.