Sandpile.org - Archive of technical x86 processor information and downloadable documentation. Includes a discussion forum. x86.org - Lots of information about x86 processors, including undocumented opcodes and bugs. Win32 Assembler Coding Tutorial - Covers MASM, TASM, NASM used with Win32, DirectX, multimedia. Especially for Games and Demos. Has sample code. OpCode of Intel Assembler 80x86 - List of most Mnemonics for x86 with description. OOPWeb - Assembly Directory - Assembly programming tutorials, references and on-line books. All searchable and free. A20 - a pain from the past - The various forms of A20 gate control. Assembler Programming - Small but growing set of ASM tutorials: general, graphics. Barry Wilks' DOS INT 21h - DOS Function Codes - A quick reference list of DOS interrupts has been extracted from a large list compiled by Ralf Brown. A introduction to x86 assembly - Tutorial written by Gavin Estey. Hamarsoft 86BUGS List - A reference for bugs and undocumented instructions in the Intel 80x86 family of processors. Programming from the Ground Up - Book on Linux x86 assembly language programming which is available both in print and online under the GFDL license. Targetted to both new programmers and professional programmers who have not yet learned assembly language. Working in Protected Mode - How to work in protected mode guide. Linux Assembly HOWTO - Guide describes how to program in assembly using free programming tools, focusing on development for or from Linux OS on i386. By Francois-Rene Rideau 1996-1999, Konstantin Boldyshev 1999-2002. Ralf Brown's Interrupt List - List of i386 specific information for IRQ's, and I/O addresses. Intel Processor Manuals - Official Intel Architecture Optimizations Manual, Intel Architecture Software Developer's Manual, Pentium Processor Family Developer's Manual. Intel Assembler CodeTable 80x86 - Overview Mnemonics - Short overview containing all instructions (transfer, arithmetic, logic, jumps), a diagram of the registers (EAX, EDX, ECX, EBX), demo program, fits to one single page, download, free