jim said:
Thanks for that followup. I am changing from a single core to a dual
core processor. Does the repair install/install over do it or does it
have to be a clean install?
The tricky part in moving an OS boot disk from one computer to another, is
the driver used to read from the hard drive and boot the computer.
Say, for example, the current motherboard has an Intel chipset. And the
new motherboard has a VIA chipset. The Intel chipset may have been
able to use the Microsoft default IDE driver. If the VIA chipset
doesn't use that driver, then the system will not be able to
boot.
Being able to boot is the largest obstacle. If the OS cannot read
from the hard drive, that pretty well limits the chances of
success.
A repair install, offers the opportunity to press F6, and install any
driver needed to allow the hard drive to boot. That is why a repair
install is recommended, when someone doesn't know the driver situation
in great detail. The odds that the repair install will help, are much
better than just changing motherboards and trying to boot.
I've managed to move my boot drive, from one motherboard to another,
because I knew the default Microsoft driver being used, works with
both of the old and new chipset. The OS did boot, and I was presented
with a large number of "new hardware" dialogs for my trouble. It took
a couple hours of installing drivers for things like NIC, sound and the
like, to finish the transition. Many, many reboots. (My OS is Win2K.)
So that covers motherboard changes.
1) No repair install, if you know what is going on with the storage
driver. It might just work.
2) A repair install can help, if the storage driver needs to be changed.
Better odds of the transition working, if you know what driver to use
via F6.
3) A total reinstall helps, if the results of your efforts are screwed.
For example, I couldn't get texture acceleration to work properly,
after a motherboard upgrade, no matter what I tried. So I did a total
reinstall to fix it (because I ran out of experiments to try).
You should always be prepared for trouble, when doing stuff like this.
I like to clone the boot drive (make an exact copy), so if the motherboard
transition doesn't go well, I can try again. Backups are a good thing
to have. If I buy a new motherboard, I buy a spare disk at the same
time, to clone the old boot drive for backup reasons.
*******
For a single to dual core processor upgrade, a HAL change is needed,
to start with. If you go to Device Manager, and check the properties
of the "Computer" entry, it might say something about "uniprocessor"
and "ACPI". The HAL needs to change to multiprocessor, so that the
additional cores can be used. Doing a "driver update" for the computer
entry, can fix that for you. So that kind of HAL change, between
ACPI HALs, should work fairly easily.
On my PC, I can simulate some of these issues, by disabling
Hyperthreading on my P4 processor. That is how I've examined
uniprocessor and multiprocessor HALs. My processor looks
like two cores, when Hyperthreading is enabled.
If the HAL listed is "Standard PC", and you get the "it is safe to
turn off your computer" message at shutdown, then changing the HAL
will be virtually impossible. But most people haven't installed
their OS, crippled like that. (I managed to do it once, due to
using a BIOS with broken ACPI implementation. Most of the time,
the OS install will do the right thing, and use some version of
ACPI HAL. I believe Windows also has some function key you can
press during install, if you want to use a different HAL than
what the OS installer would use by default. It obviously
cannot install a HAL which is incompatible with the hardware
it finds, so I couldn't force it to use ACPI on a motherboard
with a broken ACPI BIOS implementation.)
Some of the HAL options are mentioned here.
http://support.microsoft.com/default.aspx?scid=kb;en-us;309283&Product=winxp
The KB may have other articles, that list the allowed HAL
transition cases, such as being screwed if it happens to be
"Standard PC".
Paul
