Don't know if it is kde4 or recent graphics hardware but I can't seemto boot and run live cd to demo pclinuxos anymore.
Example machine at hand: Emachine laptop with 2G memory, 2.2Ghz celeron 1k cache, intel cantigia graphics, 64M.
usb or live cd of lxde and kde 2012 boots for quite awhile then hangs on either total black screen, or login.
If using XFdrake, it says to reboot.
tried vesadev, safeboot, etc.