I'm in MS Beta.. Longhorn is schedualed for Setp 2006 currently.. may be pushed back to Dec 2006..
Longhorn is designed for a 64 bit Hardware config.. complete 64 bit Motherboard and CPU and Vid Card and so forth.. however it supports 24 bit, 32 bit and 64 bit hardware / software..
16 bit or less software and hardware are not supported...
Should be a minimum of 256 MB DDR2 mem (512 MB DDR2 for most smooth performance while operating other programs inside the shell for stability.. namely for games) and a P IV with HT to run Longhorn on a 32 bit with 833 Mhz FSB... Unknown what the minimum specs are on a 64 bit system, MS has not stated as of yet. It has been tested on older systems and has run stabily, but it is not recommended as it makes the CPU work harder..