One thing to point out is that AIX is just IBM's UNIX system for supercomputing and OpenSolaris is also based on UNIX, which means while technically they don't run Linux, they are effectively cousins to Linux. Thus in reality there are just 5 computers on the top 500 list that actually run something other than Linux (or one of its cousins).Also, I find it interesting that some of the computers made by IBM actually use Intel chips.
Quantumleap42, Good points and yes, I also got a kick out of seeing that IBM makes more machines than use IBM chips. :)
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