This has proably been answered before but I can't find a reference to it. The situation is as follows:-
I have a working 160Gb hard disk taken out of an Acer machine which I don't have anymore. I have upgraded to a new Acer which is pre-installed with Vista. However my wife has a number of very expensive embroidery applications which are incompatable with Vista only running on all variants of XP and no chance of a patch being issued, they want us to shell out £950 on a complete new version of the software. The new machine will boot from a USB caddy, so my solution would be to keep the new hard disk in the system with Vista on it and to boot when needed from the old HD as a USB drive. This way I don't violate any warranty conditions. However what do I have to do to ensure the old hard disk will boot in the new system? I know drivers will not be the same but there must be a way around this. It will be a real hastle to have to wipe the new HD, loose Vista and re-install XP and all the old applications, or to just keep the new HD with Vista and fit the old HD in the case and again re-install.