Sorry to read that you're having so many problems.  I used to build computers and I'm sure the principles are the same just haven't done it in a LONG time.  I bought a pre-built (HP) and basically have just replaced things as I saw fit (put in new video card, power supply, etc).

I can't really contribute anything that hasn't already been said or mused over but sorry you had lost everything, it's always an awful experience. :(

Oh and I'm a luddite too.  I always wind back up on XP and actually pleased about it.

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