The main difference between 2003 and 2008 is Virtualization, management.
2008 has more inbuild components and updated third party drivers.
Note: Windows server 2008 45 time fast compare to win 2003.
In Windows Server 2008, Microsoft is introducing new features and technologies, some of which were not available in Windows Server 2003 with Service Pack 1 (SP1), that will help to reduce the power consumption of server and client operating systems, minimize environmental byproducts, and increase server efficiency.
Microsoft Windows Server 2008 has been designed with energy efficiency in mind, to provide customers with ready and convenient access to a number of new power-saving features. It includes updated support for Advanced Configuration and Power Interface (ACPI) processor power management (PPM) features, including support for processor performance states (P-states) and processor idle sleep states on multiprocessor systems. These features simplify power management in Windows Server 2008 (WS08) and can be managed easily across servers and clients using Group Policies.
Windows Server 2008 introduces Hyper-V (V for Virtualization) but only on 64bit versions. More and more companies are seeing this as a way of reducing hardware costs by running several 'virtual' servers on one physical machine. If you like this exciting technology, make sure that you buy an edition of Windows Server 2008 that includes Hyper-V, then launch the Server Manger, add Roles.
Windows Server 2008, formerly codenamed Longhorn, is no leas than 45 times faster than its predecessor, Windows Server 2003, in terms of network transfer speeds. Now whatever the perspective is on Microsoft's last 32-bit server operating system, the fact of the matter is that faster transfer speeds for of up to 45 times is quite an evolution compared to Windows Server 2003. Back in June 2007, Microsoft commissioned a study to the Tolly Group focused on the networking performances of its latest Windows client and server operating system, which ended up as the "Enhanced Network Performance with Microsoft Windows Vista and Windows Server 2008" whitepaper. The paper pointed to the fact that both Vista and Windows Server 2008 managed to offer "Dramatic network performance benefits".
Read more: What is the difference between server 2003 and 2008 in the functions and services? ' Answerbag http://www.answerbag.com/q_view/559903#ixzz18uM0qGWP
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