Hallo,
Quote... and with cd not at all who I format with cd then has to install it again and again ....
Uh, nonsense. With a "normal" installation, where you can format your HD at the same time (so that everything is "clean"), you install once ..... then that's it.
(until the next "crash")
Have a look here: This is how it works: Install Windows 7, XP and Vista - COMPUTER BILD