Well, there's also another proof that Windows 2000 for AXP64 exists. It's on txtsetup.sif. Code: [SourceDisksNames.axp64] 1 = %wkscd%,\cdrom_xp.5,,\axp64 7 = %wkscd%,\cdrom_xp.5,,\axp64\lang\jpn 8 = %wkscd%,\cdrom_xp.5,,\axp64\lang\kor 9 = %wkscd%,\cdrom_xp.5,,\axp64\lang\cht 10 = %wkscd%,\cdrom_xp.5,,\axp64\lang\chs 11 = %wkscd%,\cdrom_xp.5,,\axp64\lang\ara 12 = %wkscd%,\cdrom_xp.5,,\axp64\lang\heb 13 = %wkscd%,\cdrom_xp.5,,\axp64\lang\tha 14 = %wkscd%,\cdrom_xp.5,,\axp64\lang 15 = %wkscd%,\cdrom_xp.5,,\axp64\lang\ind But sadly, it was never released or leaked. It would be cool to see Windows 2000 for 64-Bit architecture. Also I know it's kinda irrevelant. However, I found entries for Windows XP x64 build 5.1.2600 aswell. Code: [SourceDisksNames.amd64] 1 = %cdname%,%cdtagfilem%,,\amd64 7 = %cdname%,%cdtagfilem%,,\amd64\lang 8 = %cdname%,%cdtagfilem%,,\amd64\lang 9 = %cdname%,%cdtagfilem%,,\amd64\lang 10 = %cdname%,%cdtagfilem%,,\amd64\lang 11 = %cdname%,%cdtagfilem%,,\amd64 12 = %cdname%,%cdtagfilem%,,\amd64 13 = %cdname%,%cdtagfilem%,,\amd64 14 = %cdname%,%cdtagfilem%,,\amd64 15 = %cdname%,%cdtagfilem%,,\amd64 55 = %cdname%,%cdtagfilem%,,\i386 56 = %cdname%,%cdtagfilem%,,\i386\lang Taken from Windows XP Pro SP3 x86. You can check on txtsetup.sif file if you don't believe me. Sadly, it was never released too. But I think it would be pretty much the same as IA64 version (IA64 branding, no themes, no Welcome screen etc.), except it's installed on AMD64-based PCs.