re quadra marginal video in article apr galileo cc rochester edu carlo merlin cvs rochester edu carlo tiana writes we are having a problem with a quadra that has stumped a couple of techs sent to us by the vendor as well as us this quadra is stuffed with mb ram mb vram and some large disk mb i think what happens is that after a certain variable interval of time the video circuitry loses vertical sync it is quite apparent that the mac cpu is still ok and the problem really seems to lie with the video circuitry since you can still save your documents quit your aplpications even pull down menus etc only the display is scrolling lik crazy so it s pretty hard to hit menu items other info deleted has anyone any ideas please please email as well as posting cause i seem to be spending a lot of time rebooting my mac lately and have a lot less time available to read news are you sure it s not a problem caused by software i ve seen this sort of effect when a runaway program which could be caused by an init conflict for instance accidentally wacks on a register in the video hardware have you tried booting with no extensions and then letting the q just sit there in the finder you might also want to try changing to bit addressing yes i know you can t access your full mb of ram it s just an experiment as the video hardware registers can t be accessed then another thing to try as a recovery measure is to use something like quickkeys to change the pixel depth of the display this reprograms some of the video hardware registers and may allow sync to be restored dale adams
