However, because of the maturity of their technology and management infrastructure, mainframe and Unix server deployments are able to run at higher utilization levels.

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More than 20 years ago, HP introduced the first successful commercial UNIX server, the HP 9000 Series 840, as well as the first x86 server, the HP SystemPro.

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"No one runs large, million-hits-per-day Web sites on Linux, " Occleshaw said, adding that IBM would still recommend its AIX Unix-based server to customers that wanted to run large, serious enterprise applications.

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The campaign, which includes rebranding Digital Unix and launching new Alpha-based server products, is Compaq's latest effort to grow Unix market share.

CNN: Compaq wants in on the Unix market

Moving from the NT server field to Unix, as Compaq intends to do, won't result in a mixed sales pitch from the company, Yeates said.

CNN: Compaq wants in on the Unix market

Features include name-and-password log-in support, file and directory caching for quick access, firewall and proxy-server support, and UNIX file attribute support.

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The Compaq Tru64 Unix brand will be extended to cover future server products, Yeates said.

CNN: Compaq wants in on the Unix market

The chip is designed for high-end servers running the Unix operating system and has been launched with a new server designed around it.

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In 2001, Caldera acquired the server software and services businesses of Santa Cruz Operations, a Unix software company founded in 1979, using money from a successful IPO.

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If users want to use Raw Iron database servers in place of SQL Server on NT, it isn't much different than using Unix or Linux underneath, he said.

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