Hello, not that it's a real threat to the pc, but it would come in handy to learn about. I replaced Windows 7 by Linux Debian +KDE 64bits yesterday on one of the lab computers in the class room (well, the pc's are part of the lab itself). Then today I wanted to replace Debian by Kubuntu (also 64 bits of course) but the installation is very slow with crash errors in each step, of each step (time zone, keyboard settings...). Now it's just standing there on the final screen. Is there something I had to take into account first? Oh, the second USB-stick I used for it was USB3.0, though I don't think that makes a difference.