Not entirely sure what you mean, but I <i>think</i> you're reffering to the fact that the AMD64 has native support for 64-bit operation, but nothing yet takes advantage of this because you'd need a 64-bit version of windows, which microsoft hasn't yet released.
However, it's still a truly excellent 32-bit performer, so this really isn't an issue.
If I was building a rig now, I'd buy an A64.
[Edit]
Oh, I know you can get 64-bit versions of Linux, before anyone yells about that...
[/Edit]
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Epox 8RDA+ V1.1 w/ Custom NB HS
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Sapphire 9800Pro (VGA Silencer Rev3) @418/742<P ID="edit"><FONT SIZE=-1><EM>Edited by ChipDeath on 08/18/04 09:46 AM.</EM></FONT></P>