On: Say hello to x64 Assembly, part 1

[CraigJPerry]

Another great resource, albeit for x86 rather than 64 http://savannah.nongnu.org/projects/pgubook/

[pekk → CraigJPerry]

It isn't nearly as hard to find x86 guides as x86-64 guides.

[0xAX → pekk]

That's why i started to write it :)

[CraigJPerry → pekk]

In what material way, in the context of a beginners guide, are they different?

Calling convention, word size and the r- prefixes. If you compete the PGU book (you could just write 32 bit code if you want), these are trivialities.