SANTA CLARA, Calif. -- August 25, 2004 �� In the second quarter of 2004, Sun Microsystems, Inc. (Nasdaq: SUNW) achieved significant revenue and volume growth in almost every category. Sun outperformed all vendors in revenue market share growth on a quarter-to-quarter (Q/Q) basis including All OS, UNIX+Linux and UNIX, as reported in the 2Q04 Worldwide Server Database report by Gartner Dataquest, released this week. Year on year, Sun outpaced all competitors in unit shipment growth at 38.4%, and gained market share against key rivals.

Sun's performance was fueled by strong demand for Solaris servers with UltraSPARC IV and Opteron processors, and Netra 240/440 systems, and primarily from customers in financial services, communications and government markets.

In the UNIX+Linux market, Sun outpaced all vendors Q/Q both in revenue and unit market share, leading in both categories. Sun's sequential UNIX+Linux growth is reflected in its revenue market share gains: a 6.0 point increase for Sun, in contrast to the nearest competitor which grew only .1 point.

In addition to its market share gains, in actual Q/Q growth for All OS Sun significantly outperformed all competitors.

"We're demonstrating not only significant unit volume gains, but are backing it with strong revenue gains��an indication that our expansion into the low-end market with Solaris is taking hold, complementing our stronghold in the traditional systems market," said Larry Singer, Sun's senior vice president and strategic insights officer. "Customers are snatching up the new Solaris servers we've introduced this year, and using them as engines to run Solaris and the Java Enterprise System. And the increased unit volume is allowing us to capture more ISVs and expand our footprint in the enterprise��creating a vehicle for long-term product and services revenue growth."

Key Growth Metrics

Sun demonstrated significant growth and outpaced competitors in a number of key areas, including:

• -Sun increased All OS platform server unit shipment market share both on an annual (Y/Y) and sequential (Q/Q) basis.
• -Sun gained more UNIX platform server unit and revenue market share both Y/Y and Q/Q than all other Top 5 vendors combined.
• -Sun grew more revenue and unit market share both year-to-year (+2.2 and +7.0 points respectively) and sequentially (+7.8 and +4.7 points respectively) in the UNIX platform server market than any competitor, while maintaining its leadership position.
• -Opteron and UltraSPARC processor shipments and revenue both increased Q/Q and Y/Y, while Itanium server shipments declined Q/Q.

About Sun Microsystems, Inc.

Since its inception in 1982, a singular vision -- "The Network Is The Computer" -- has propelled Sun Microsystems, Inc. (Nasdaq: SUNW) to its position as a leading provider of industrial-strength hardware, software and services that make the Net work. Sun can be found in more than 100 countries and on the World Wide Web at http://sun.com

Sun, Sun Microsystems, the Sun logo, The Network is the Computer, Solaris, Netra and Java are trademarks or registered trademarks of Sun Microsystems, Inc. in the United States and other countries.

UNIX is a registered trademark in the United States and other countries, exclusively licensed through X/Open Company, Ltd.