Hi, sorry for registering just to ask for your help! Somebody over at a Linux forum recommended this site to me and said I might find somebody who knows an answer to my problem! Overview: I dualboot Windows XP Home (32-Bit) US version and Ubuntu 8.04 (amd64) German version. I do not use a pirated copy but an OEM CD. I have preinstalled drivers and SP3 with nLite. Windows worked without any problem for 3 months now. I have Kaspersky Internet Security 2007 set to maximum security. I updated graphics drivers once* (two days before Windows crashed) - I haven't changed the system any other than that! * NVIDIA PhysX System Software Problem: One day Windows just wouldn't boot anymore. Instead of loading the login screen the PC just rebooted and sent me back to Ubuntu's GRUB loader. Loading the last working configuration for Windows didn't change anything. I can boot into Safe Mode but there's not much I can do. I tried running Kaspersky to search for a virus but it reported it can't do much in Safe Mode. All I can do is use system restore. So that's what I did. To my dismay I had to find out that Windows' System Restore DOES remove and alter files, although it clearly says that it does not! However, Windows loaded back normal again - just some files went missing. But hell, next restart XP won't boot again. I try System Restore again but it does not work this time - XP reboots before showing the login screen. I try loading an even older configuration with System Restore and it boots up again, losing more data on the way (some new files remained, though). I tried changing couple of settings and uninstalling everything I do not need. Next restart it still won't boot anymore. I got really upset at this point! I'm ready to format and reinstall XP and insert the original Windows CD... (Ubuntu still works without any problems - I'm using it now!) "Press any key to boot from CD..." "Please wait while setup configures your hardware..." Black screen. No answer. I waited for 30 minutes. The red light indicates that the system is trying to do something but I don't recall waiting longer than 3 seconds for the setup screen to appear. Pressing the power button results into a restart but the CD still won't access the setup. I've also tried the nLite tweaked version of my Windows CD but nothing changed! I also tried my girlfriend's copy of Windows without success. Short: I can boot neither Windows nor the Windows Boot CD! I can keep system restoring my PC but on the way I keep losing more and more files and it will only work until I restart! My guess: Windows loads in Safe Mode but it reboots as soon as it's supposed to make use of the graphics card. I fear that the newly released Nvidia PhysX drivers jacked my graphics accelerator. Windows doesn't let me remove the drivers in Safe Mode, though. What makes little sense to me is that I could reboot several times after installing the new drivers and that the card has absolutely no problems under GNU/Linux (using Compiz-Fusion), yet the Windows CD has problems recognizing the hardware... Your help is greatly appreciated!