Sun-Oracle x86 server combo tops the SAP charts

"Sun's top-end Opteron boxes put a single processor and its memory on a single board, eight of which plug into the server backplane; the whole shebang takes up only 4U of rack space, making it one of the most compact eight-socket servers around.

The X4640 that Sun tested was equipped with Solaris 10 and the Oracle 10g database, and it was able to support 10,000 users on the two-tier SAP sales and distribution (SD) benchmark test. The two-tier version of the test puts the application and the database that the applications pound on inside a single box, rather than breaking app and database servers into separate machines as three-tier setups do..."