Config: HP Pavilion 6553, Win 98SE, Celeron 466Mhz on an Asus Mew-VM w/ob-vid,192 MB Ram, 20GB Seagate HD.

Here goes from the top, I get called in by a client to clean up his comp (Adware/Spyware etc.) and its in such terrible shape I recommend format and re-install of Win 98SE. I install OS without any problems and he also wanted Norton AV, which I put on with no problems. Got on internet and downloaded updates for norton and installed them. Re-start comp and voila", comp won't complete post. It just hangs on the HP "Epanding Possibilities" boot screen. Can't get into bios or even get comp to boot with win 98 start-up floppy. Bring comp back to office to run a more thorough series of tests. Checked all connections, look OK, put in another PS still won't boot. Put in another 128 MB chip, slot 1 & slot 2, still a no-go. Moved HD to a test bed sys. goes right into win 98. So HD's not the problem. Diagnostic card gets hung up on post code "A2" which according to manual for phoenix bios v4 is a "Check Key Lock" error. Problem is that comp doesn't have a key lock. It has the pins on motherboard but no key lock attached. Testing has been with a bare minimum config. Removed motherboard from case, disconnected all drives except HD, 1 stick of ram etc. What I think is unusual is I get no post beeps at boot failure. Well this is a rather long post and I probably left out certain things I have done but, any help would be greatly appreciated.

See if this helps:
http://www.pcguide.com/ts/x/comp/case/key.htm

Thanks Ski for the quick response. I saw that link earlier and checked it how as thoroughly as I could. What gets me is why would I get this error on 2 motherboards in a row? The pins are there for the key lock but, no key lock has ever been attached to them.

You may want to start from square 1, and reformat and reinstall Windows.
However, it looks like you will have to reformat the HD in a different system.

Thanks Ski, I will give that a try.

You may want to start from square 1, and reformat and reinstall Windows.
However, it looks like you will have to reformat the HD in a different system.
Formatted and re-installed windows 98 but, still won't complete post. Keeps hanging on "A2" post code. I've ordered a new motherboard and a used CPU from Compgeeks. If this doesn't work I'm throwing in the towel.

Well, I got new MB and hooked it up and was able to boot into bios and set to defaults. Then booted up into window 98 and everything looked good. Ran all windows diagnostics that I could (scandisk, defrag, system file check etc.) and checked hardware in system properties. System files were ok and hardware looked good. Re-booted and blasted machine won't boot. Hangs on HP boot logo. "Theres something happening here and what it is ain't exactly clear" to quote a 60's anti-war song. Help! :confused:

"Theres something happening here and what it is ain't exactly clear"
'For What It's Worth', by Buffalo Springfield, 1966.
I remember it well(And saying that dates me).

Reformat the HD, and reinstall Windows.
This is recommended whenever a new MB is installed.