Is not a compaq armada is a balance

most hp/compaq laptops will have memory slots located under the keyboard, and sometimes an additional memory slot accessed through a panel on the bottom of the notebook.
In your case, you have 2 memory slots located under the keyboard. Officially, this unit only supports up to 256 mb memory modules for a maximum of 512 MB of memory so if you already have that, be aware that larger capacity memory modules may not work.

I'm copying someone else's answer; I can't vouch for it.
emove the main battery and mains power supply, hit the power switch to drain any retained charge. then remove the cmos battery and short out the contacts. the cmos battery is on the right under the panel at the top of the keyboard, which can be popped out by gently levering it up at the edges. the key board can then be folded clear, watch for the ribbon cable under it that connects to the motherboard.

You don't remove the keyboard to remove the HDD. It is accessed on the edge of the left side of the unit.

Here is a link to a pdf file showing how to do it:

Armada HDD Replacement

Try to check your USB maybe there be breaks that can't be seen,try to use new cable..

Hope this may help;

Regards,
VOTIT

DON'T FORGET TO RATE:

It looks like your keyboard is wrongly configured, go to control panel, keyboard and set it to standar (101 or 102) keyboard. Also check your local (regional and language) settings are set to correct country.

Let me know if this solved your problem.

You need to download and install the proper drivers from Compaq (now HP). Go to http://www.compaq.com and do the following:

Click "Get Support" at the top.

Enter "armada m700" in the "Enter a product number" box.

Click the little submit button that looks like ">>".

Click "Download drivers and software".

Click one of the "Windows XP" links. Doesn't matter which one.

Scroll down and click the "Download" buttons that correspond to each driver you want to download.

Install the drivers you downloaded.

you should first download this manual. i believe you need to remove the keyboard....which is fairly simple if you have a small screwdriver.

http://www.eserviceinfo.com/index.php?what=search2&searchstring=Compaq+Armada+E500+and+Armada+V300

They needs to be replaced or clean! at authorised service station!

try typing:

D:/SETUP

don't forget the colon after D

if this does not work, then try typing:

E:/SETUP

Here you go
All you need is here.
http://h10032.www1.hp.com/ctg/Manual/c00246219.pdf