Ubuntu 12.04 Alpha 2 amd64 CD can be used only with 64bit PC. The Precise Pangolin Alpha 2 Release of Ubuntu 12.04 is a developer snapshot to give you a very early glance at the next version of Ubuntu. Ubuntu 12.04 Alpha 2 i386 CD is the second alpha release of Ubuntu 12.04, code name "Precise Pangolin". Alpha 2 is the second in a series of milestone images that will be released throughout the Precise development cycle. This is the first Ubuntu milestone release to include images for the armhf architecture, for the ARM CPUs using the hard-float ABI. New packages showing up for the first time include Linux Kernel 3.2.2, Upstart 1.4, Unity 5.0, LibreOffice 3.5 beta 2.
About Ubuntu
Ubuntu is a complete desktop Linux operating system, freely available with both community and professional support. The Ubuntu community is built on the ideas enshrined in the Ubuntu Manifesto: that software should be available free of charge, that software tools should be usable by people in their local language and despite any disabilities, and that people should have the freedom to customise and alter their software in whatever way they see fit. "Ubuntu" is an ancient African word, meaning "humanity to others". The Ubuntu distribution brings the spirit of Ubuntu to the software world.