P4P800E boots from ext. USB drive after Mirroring drives


Ed O

I have a P4P800-E Deluxe motherboard.
Originally had 2 P-IDE drives on the primary IDE channel as C: and D:
An IDE cdrom on secondary IDE channel and an external USB 2.0 drive.

I bought 2 SATA drives.
Mirrored the two P-IDE drives to create the C: drive
Mirrored the two SATA drives to create the D: drive.
Had to set the boot sequence in BIOS to boot from the mirrored P-IDE drives.
(Went through a bunch of steps to move the data, built array from exising
data, etc)
All is well, boots from the original Win-XP image which is mirrored.

BUT, when I boot with the external USB drive attached and on,
it wants to boot from the USB drive. I have to turnoff the USB to
boot, then turn it on afterward to access it.

Any way to not have it try to boot from the USB drive?


P.S. could I have used one P-IDE and one SATA as a mirror set
and done the same with the other P-IDE and SATA drive?


Any help with this would be great 'cause I have a similar problem; in
fact, mine is even a bit more strange:

I have a ZIP-drive that's randomly used on my regular PC and my laptop,
so sometimes it's connected to the pc while booting and sometimes it's not.
When the ZIP was NOT connected the last time I booted the computer and
then I boot the next day with the ZIP attached to the P4P800 again the
ZIP is automatically inserted as "Primary Boot-Device" in the bios,
shifting my DVD from pos. 1 to 2 and the harddisk from 2 to 3. (Usualy I
have my DVD as first and HD as second boot-device).

My ZIP-disks are not bootable, so the systems says "invalid or no boot
disk". OK, so I remove the drive and reset the computer. It should start
now correctly, BUT:
After revmoving the ZIP my other devices are NOT moved back into their
original status!?! The DVD becomes first, which is OK, but the HD is
REMOVED from the boot list (2nd and 3rd boot device show up as emtpy in
the bios when checking that). Obviously, the system does NOT boot at all
because it does not "see" the HD as a bootable device (btw, IDE-type, no

So, each time I remove and reattach the zip drive to my PC from the
laptop (which happens at least each weekend) the boot-settings of the
bios are f**** up and I have to enter the setup to correct the settings

I tried to disable "legacy usb support" which seemed to work on first
view, but then some of my other USB devices don't work correctly under
XP (SP2); esp. printer and scanner :-(((

I also tried to use an admin-password, but that did not help - the
settings were still changed "silently" by the bios without notification :-(

How can Ed O and me lock the list of boot-devices to prevent this USB

Berlin, Germany

Ed O


Lets hope for an answer. At least my boot sequence does not seem to change
in the bios. Wonder if we have the same bios version. Unfortunately this
machine is at a client's business(thus the mirroring) and I cannot check the
bios version which does not seem to change... but being it is their
server, they now only power up the PC with the external USB off, then after
up, they turn it on.

For IDE drives the discovery is set to auto in the bios, wonder if it is
changed to
whatever settings, and the unused IDE are set to NONE, if it will prevent
the MB from trying to find other devices?

Ed O

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