&os;/i386 runs on a wide variety of IBM PC compatible machines. Due to the wide range of hardware available for this architecture, it is impossible to exhaustively list all combinations of equipment supported by &os;. Nevertheless, some general guidelines are presented here. Almost all i386-compatible processors are supported. All Intel processors beginning with the 80386 are supported, including the 80386, 80486, Pentium, Pentium Pro, Pentium II, Pentium III, Pentium 4, and variants thereof, such as the Xeon and Celeron processors. (While technically supported, the use of the 80386SX is specifically not recommended.) All i386-compatible AMD processors are also supported, including the Am486, Am5x86, K5, K6 (and variants), Athlon (including Athlon-MP, Athlon-XP, Athlon-4, and Athlon Thunderbird), and Duron processors. The AMD Élan SC520 embedded processor is supported. The Transmeta Crusoe is recognized and supported, as are i386-compatible processors from Cyrix and NexGen. There is a wide variety of motherboards available for this architecture. Motherboards using the ISA, VLB, EISA, AGP, and PCI expansion busses are well-supported. There is some limited support for the MCA (MicroChannel) expansion bus used in the IBM PS/2 line of PCs. Symmetric multi-processor (SMP) systems are generally supported by &os;, although in some cases, BIOS or motherboard bugs may generate some problems. Perusal of the archives of the &a.smp; may yield some clues. &os; will generally run on i386-based laptops, albeit with varying levels of support for certain hardware features such as sound, graphics, power management, and PCCARD expansion slots. These features tend to vary in idiosyncratic ways between machines, and frequently require special-case support in &os; to work around hardware bugs or other oddities. When in doubt, a search of the archives of the &a.mobile; may be useful.