BIOS reset jumper

then can I alternatively find out the 2 points to be short circuited?

Maybe, but I won't try to tell you, not having seen a Omnibook mobo, I don't know if the blank solder spots are even there.  Can you take the CMOS Battery out?

If this is a password problem, then read this?

Appendix B - Hewlett-Packard Password

Removal Policy
If the user forgets the system password, there is a master password that will
unlock the OmniBook. The user calls Technical Support to determine this
master password as follows:
1. Support will tell the user the keys to type at the password entry screen:
[Alt][Shift][f10]
2. The OmniBook generates and displays an encoded master password.
This is displayed under the normal password entry area. At this point, this
is the only password that will unlock the OmniBook unless the user
presses [ESC] to remove the encoded master from the password entry
screen. Then the user's stored password can be entered.
3. The user reads the encoded master password to Support.
4. Support runs a program that decodes the encoded password, and reads
the decoded password (alphanumeric) to the user.
5. The user types in the decoded password.
6. OmniBook decodes the encoded master password it generated and
compares it to the decoded password typed in by the user.
7. If the two passwords match, the OmniBook is unlocked. The forgotten
password is automatically erased. Support can then guide the user
through the process of entering a new password.
8. If the two passwords do not match, the previous sequence must be
repeated until the user correctly enters a master password.
The encoded master password is an eight-character alphanumeric sequence
that the OmniBook generates at random every time the appropriate keys are
pressed in the password entry screen. Because it is generated randomly, a
master password can only be used to unlock the OmniBook once. If the user
forgets the password at another time, it will require another call to Support. (If
the user presses the appropriate keys by mistake, pressing [ESC] will allow
entering the stored password.)
The password descramble programs for the HP OmniBook Notebook PCs are
protected as HP Company Private information. They may not be copied,
backed-up, printed or distributed. There are only six official copies of each
program.
In addition to the program being protected, its use is also controlled. Hewlett-
Packard and authorized support providers must ensure with written evidence
that the OmniBook that is being "descrambled" is actually in the hands of the
unit's actual and current owner. This requires a sales receipt showing the unit
serial number and owner's name, or a written statement from the owner
attesting that he or she is the owner of the unit. The statement can be a fax
copy of the document. The fact that the unit is in the hands of an HP
representative on behalf of the customer is not evidence of ownership. In
addition, HP will not descramble a unit for any non-owner, even if it involves
law enforcement agencies. If you receive such a request, you should notify
management and HP Corporate Legal immediately. (These requests may
require a court order prior to our participation.)
Further, you must log the name, serial number and date of the running of the
descramble program, and file the written backup with the log. The log and
backup are subject to standard record retention process and review.
The final issue relating to descramble of passwords is that HP cannot provide
information to users that would assist them in improperly descrambling a
password and opening a unit.

usually if there is no jumper it's best to pull the battery (mobo, not laptop battery) and  leave the system off for 20 min. or so.  that should reset it in most cases.

Yeah, pull out the battery.  Also, you can hold "Insert" as the computer starts up.  Thanks, Beef.

to coral47: I had read the appendix before, that's why I asked this to bypass it. I bought it from an auction so I can't use the HP service to get the password. The requirement is so strict. Even contacting an HP dealer won't help.

To AlbertaBeef: what if you can't even find the battery?
Pls have a check yourself at http://24.237.160.4/files/omnibook/ob800/FAQs/inside_pics/

to radomirthegreat: what magic could that "insert" do?

"Insert" is another way to reset the BIOS.  That's all.  It works on some systems, but not all.  It depends on the motherboard, and I don't know where to find specific details concerning this information.

to radomirthegreat: if you can just use "insert" then there is no need to use pswd. At the moment my omni is still disassembled so I can't try but I believe after you press Insert then you will be asked for a pswd.

finding the previous owner is not possible. this is not a car. I will try your list anyway later. But it is better if someone knows there is a reset jumper or 2 points to be shortcut to remove the pswd.

I downloaded a couple of your pics for another look later, but I didn't really see anything I could tell you yet. The area above the video chip looks promising. There are some jumpers and red buttons (?) there.  Do you have the manual, and does it say anything about these? Can you tell which is the BIOS Chip? ( look for AMI, AWARD, PHENIOX, etc. )

to coral47: for the manuals: http://24.237.160.4/files/omnibook/ob800/HP%20OmniBook%20800CS-CT%20-%20Service%20Manual.pdf and http://24.237.160.4/files/omnibook/ob800/Manuals/
Sorry, I still need to have a good look myself at them but at the very least this omni looks quite different than the other notebooks.

I can't find anything useful in the manual or in the pics.

You could try fighting with HP by telling them your story, and see if they will work with you ( Ebay should have some kind of record of the transaction? )

Or maybe getting another BIOS chip. There are places on the web that sell them.
You might be able to find a dead/wounded laptop at a repair shop, flea market, yard sale, or someone who deals in used computer parts. Maybe a 'wanted' ad on a postup board or in the classifieds.

Think of it as a treasure hunt.  Any which way, it will be a learning experience.

to coral47:

Regarding your suggestion of "figthing with HP", here is an article of how Dell has an "unshakable policy" of returning address: http://www.smh.com.au/articles/2003/11/04/1067708212511.html?from=storyrhs

If I send back my notebook to HP, chances are they would simply send it back to the registered owner!

At the moment, it is still disassembled, later I will try the passwords you introduce once it is assembled back.

Yeah, that is pretty rough. But I was talking about getting the Master Password over the phone, not sending the thing back to them. Probably be the same runaround though.