The Sun 540-7884 1.6Ghz 8-Core System Board Assembly (July 2009 Refresh) is in in stock at Calhoun Technologies. For over 10 years Calhoun Technologies has been saving companies likes your up to 80% off list price on hard to find computer hardware. Manufacturer: Sun Part Number: 540-7884 Details: Sun 540-7884 1.6Ghz 8-Core System Board Assembly (July 2009 Refresh)