How is the x64 architecture different from x86
64-bit, c++, x86, x86-64
Solution
In x86 there are 8 32 bit registers, in x64 the registers are 64 bits each and there are 8 more of them. The 128 bit SSE registers are 128 bits in both, but on x86 there are 8 of them while in x64 there are 16 of them. Also some instructions were cut in x64.
In x64 mode you can still use the registers as 32 bits by using their 32 bit name(starting with an 'e') instead of their 64 bit name(starting with an 'r'), and the assembly would be mostly the same.
http://en.wikipedia.org/wiki/X86#x86_registers
Or if you want some really heavy reading(like 1000s of pages...)
http://www.intel.com/products/processor/manuals/index.htm I read through a few hundred pages of those manuals and learned a lot, really good stuff.
Problem
I need to mess around with the stacks on these architecture and am really a n00b here. Any pointers to reading topics/google searches that i can do. I am looking for how these architectures are fundamentally different from each other. something more than the wikipedia article on this topic http://en.wikipedia.org/wiki/X64