Hyperthreading hurts 5.3?

Giorgos Keramidas keramida at ceid.upatras.gr
Wed Jan 12 03:24:00 PST 2005


On 2005-01-11 22:18, Chuck Swiger <cswiger at mac.com> wrote:
>David Kelly wrote:

>>> (disabling HT will apparently mean I have to reinstall XP on the
>>> other drive.
>>
>> What does XP have to do with it? IIRC on Dell its F2 during the
>> power-on diagnostics to reach the built-in BIOS config. That is where
>> HT is to be disabled.
>
> If you install and configure many flavors of Windows on a SMP system,
> that installation will not work if you move that image to a uni-proc
> system by swapping disks or otherwise removing CPU's (ie, by turning
> off HT'ing).  I last saw this with a Win2K system, which immediately
> blue-screened with an "invalid SMP HAL" error very early in the boot.

Moving a disk with Windows installed on it to another system has other
problems too, although they are not (in general) as serious.

Since the user doesn't have the source, many options are 'tuned by the
installation process' to the system Windows is installed on.  So it
doesn't sound as surprising that it would require a reinstall when HTT
is toggled :-)

> [ It doesn't surprise me that one would want or have to reinstall XP after
> disabling HyperThreading.  There exist even less comprehensible reasons
> which oblige people to reinstall Windows.... ]

True.



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