http://www.intel.com/support/platform/ht/os.htm
Hyper-Threading Technology? Operating Systems that Include Optimizations for
Hyper-Threading Technology
Note: Information on Hyper-Threading Technology ? for Intel® XeonT
processors is available here.
Microsoft* Windows* Operating System Desktop Based PCs
The following desktop operating systems include optimizations for HT
Technology and are currently eligible to carry the new Intel® Pentium® 4
Processor with HT Technology logo:
a.. Microsoft* Windows* XP Professional Edition
b.. Microsoft* Windows* XP Home Edition
The following desktop operating systems are not recommended for use
with Hyper-Threading Technology. If you are using one of the following
desktop operating systems, it is advised that you should disable
Hyper-Threading Technology in the system BIOS Setup program:
a.. Microsoft Windows 2000 (all versions)
b.. Microsoft Windows NT* 4.0
c.. Microsoft Windows Me
d.. Microsoft Windows 98
e.. Microsoft Windows 98 SE
Linux* Operating System Desktop Based PCs
The following Linux operating systems include optimizations for HT
Technology and are currently eligible to carry the Intel® Pentium® 4
Processor with HT Technology logo:
a.. Red Hat Linux* 9 (Professional and Personal versions)
b.. SuSE Linux* 8.2 (Professional and Personal versions)
c.. Red Flag Linux* Desktop 4.0
d.. COSIX* Linux* 4.0
Note that while other Linux operating systems may have HT Technology
enabled, only the distributions above are currently eligible to carry the
Intel Pentium 4 Processor with HT Technology logo. If purchasing a PC based
on a different Linux operating system, check with your PC vendor to
determine if the PC includes the necessary system ingredients for HT
Technology and has HT Technology enabled.
? Hyper-Threading Technology requires a computer system with an Intel®
Pentium® 4 processor supporting HT Technology and a Hyper-Threading
Technology enabled chipset, BIOS and operating system. Performance will vary
depending on the specific hardware and software you use. See
http://www.intel.com/info/hyperthreading/ for more information including
details on which processors support HT Technology.