Hi Guys, After a chat with some helpful people on Freenode I've included as much information as I can think to about this error, if you need anything else please don't hesitate to ask. I run a webserver (remotely administered, no graphical user interface that i know of - certainly not one running all the time) - in the past few days this error has started to occur, the system dies and needs manually rebooting after each occurence: ---------------- May 21 23:08:01 testmachine kernel: Page has mapping still set. This is a serious situation. However if you May 21 23:08:01 testmachine kernel: are using the NVidia binary only module please report this bug to ----------------- The machine runs CentOS 3 and has been for ~2 Years, a technician at the datacentre ran Memtest earlier today which returned no errors. Hardware wise it's an intel 2.53Ghz Celeron, 1.5GB RAM I would really appreciate any help! Henri