i get the error message "a disk read error occurred press ctrl+alt+del to restart"

i have checked all over the net. but i cannot find anything to do with my specific problem.

i have a advent 7001 laptop (the problem) and an old ibm thinkpad 600e laptop. in the advent my sister's friend disconnected the cd drive (why i dont know, he wont take a look at it again though and i dont know how to re-connect it) i can strip it down to the motherboard but the are no loose cables.

anyway because of this i have to swap hard drive between both laptops (to use the ibm's cd drive)

to start off with both laptops showed an error but i formatted the hard drive (using format in the xp recovery console) and then did a completely new installation (nothing worth keeping on the laptop, just used for internet) and now i still get the error on the advent but it works fine on the ibm (id use that but its so slow)

i tried to use the HDD out of the IBM but it got to the point where it usually says "disk read error" but instead it just shows a blank screen with a flashing _ sign in the top left.

1. does anybody know what i need to do in order to connect the cd drive the advent (it would save so much hassle)

2. even though on startup when is says "checking nvram....516096kb OK" could there still be a ram problem?

3. if it is a motherboard problem how can i test it?

4. any suggestions?

technical stuff:
hard drive: samsung MP0402H
OS: windows XP Home sp2
RAM: 512MB
Bios: American Megatrends Inc. 07.00T 04/02/01
cd drive: MATSH_ITA UJDA710 (NOTE: there is no _. without it, it would activate the swear filter)

possibly some other info i have forgotten please ask for any more details.