Really basic & n00b question:
I have an old system, I'm getting a new one. Can I just put the old HDD in the chassis and plug it in? It has XP on it with apps.. New system has HDD with Windows 7 pre-installed.
PSU isn't a problem.
Windows will likely recognize it has an OS on it and give you an option to boot to it. So you might need to take it out of the boot manager. Otherwise each boot it will ask if you which disk you want to boot to. At least if my memory serves me right....