(hint: it doesn't in most modern OSes).
Yep, that's the point. In another forum, somebody posted a school exercise with
mov eax, [bx] (probably a typo), and to my surprise, it assembled well with my default assembler, so I tried to convince Windows to accept addresses below 10000h but no cigar... so I wrote it in 64-bit code, and voilĂ ,
mov rax, [ebx] works just fine ;)