Recently the developers have been discussing the possibility of adding some additional optimizations to our i686 port to improve multimedia support. This would involve reducing the compatibility with older systems.
As some of you may have heard (, Google translation ), this discussion has resulted in the decision to focus exclusively on the x86_64 port. The overall opinion of the developers is that the x86_64 port is now complete enough to justify this decision and that this is in keeping with Arch's philosophy of supporting current generation hardware. The x86_64 architecture has been available since 2002 (compared to i686 which is from 1995), and we believe most of our i686 users have x86_64 compatible hardware.
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