On Acer it's called PQSERVICE partition, and NTFS.
I badblocked both System + Data partitions. I left PQSERVICE alone.
You can use it to restore your (Acer) laptop to factory defaults, even without a recovery DVD.
Copy Paste FROM:
https://groups.google.com/forum/#!topic/altoswindows-2k3/KLxvtdnTtTY" how to use and start boot of hidden EISA partition (contains; system factory restore files & drivers)
3 posts by 1 author
devnullius @ googlewave.com
2/3/10
Most brand computers, laptops, notebooks & netbooks come with a hidden
partion of an EISA type. Right clicking it in Disk Administrator will
not give an option or possibility to mount the unmounted drive or
assign it a drive letter.
This partition is initially used when you first power up your
computer. You then get an automated installation / image restore that
gives you a fully operating and installed Windows.
If you need to restore your computer to system factory defaults, and
you do not have the original dvd's to help you out, you might be in
luck when you saved your old EISA partition.
You can, again, boot from this EISA partition and completely restore
your computer. All original data WILL BE LOST.
More on how to do this, here:
http://en.kioskea.net/forum/affich-62937-recovery-discCopy-paste here:
" Using a Boot CD like the wonderful Hiren's bootcd, I could see 2
partitions:
- a first 800MB partition that was hidden and contained the recovery
data
- a second partition using the rest of the disk and was the active
partition.
Using any partitioning tool, I did set the first partition (recovery
partition) as the active one, applied the changes and rebooted.
That's it !!! The Laptop rebooted in a recovery mode in which I
followed a wizard and could restore the laptop in its factory settings
within 10 minutes.
No CD or DVD to buy.
Many thanks to Hiren's BootCD creator by the way !!!
Good luck ! "
And also from this page, the following:
" You can use hirens boot cd to boot into a "mini windows xp", there
you go to administrative tools and the "Disk Manager".
Within Disk Manager you can right click on the recovery partition and
"set as active"...
many thanks to zorglups for the tip with setting the recovery
partition active.
i tried to set up a windows xp on a compaq cq60-110EG. But it was very
time-consuming to find the right drivers, and i didn't manage to get a
working sound-driver. therefore i had to recover the vista system
(without a recovery-cd).
and it worked perfectly!
thanks!! "
Hiren's BootCD is a classic. If you have your own boot-warez, use it.
It makes no difference. If you do not have any recovery tool-cd's or
dvd's, install the torrent search program 'Bit Che' (excellent
program!!!).
Search for some Live cd's or Recovery cd's and make your partition
active and bootable... It should work

I still have to test for a way to quicly acces this EISA partition
once Windows is installed. I suppose it also contains drivers for all
the hardware you have. And finding the right drivers... It can be an
ass : )
Special thanks to: zorglups, on Jul 8, 2009 9:46:54 pm BST in
kioskea.net-forum.
Have fun and Peace!
Devvie
~~~ devnullius@googlewave.com ~~~
Cuisvis hominis est errare, nullius nisi insipientis in errore persevare
------
All spelling mistakes are my own and may only be distributed under the GNU General Public License! - (© 95-1 by Coredump; 2-10 by DevNullius)