The only difference is the rev 2 has updated sound.
I have the GA-8KNXP Ultra-64 which is same as rev 2, but includes SCSI also, and updated Gold DPS and ALC-850 (upgraded sound again), and I love it.
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And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign</pre><p></font color=red>