I have an old G4 powermac / imac (bought second hand/no disks ) osx: 10.5.8 powermac 6,1 powerpc G4 (3.3) processor 1 GHz memory 1.5 GB DDR SD RAM cpu's 1 version 4 Boot rom version 4.5.9f1 all of a sudden since yesterday when we swithc on we get a blank grey screen and nothing else ! Tried re-setting PRM ( hope that's right) + tried holding down shift key on start up, but nothing ! It was working fine, this is out of the blue, no new software installed or anything. Not computer savy , so would appreciate any advice in idiot proof style language. Have got a boxed version of osx 120.4 bought new ( on e bay) and happy to instal that if it will reoslve this issue. Nothing vital we need to save on this comp - it is used purely for internet surfing. Thank you.