It should be noted with laptops that if you set a 'Harddrive password' in the BIOS, it's a good idea to remove it BEFORE you clone the drive.Shouldn't be necessary - if you can boot the system and the disk password is entered, you'll be getting the right data. AFAIK, it's not like you're going to get scrambled data if you don't have an authenticated disk; you will simply be denied access to it. ATA disk passwords != full-disk encryption
I didn't say it was but on my 5 year old Acer laptop if you specify a HD password in BIOS it locks that harddrive to that motherboard
by way of the hardware IDs.
You would find that you could no longer boot the system and the data on the drive is no longer accessible by that laptop, (as normally installed), as you said.
The above caused a new motherboard AND harddrive to be installed under warranty in my laptop.
I had a HD Password set when the following happened.
The motherboard developed a fault, so it went in for repair. They replaced the motherboard, only the laptop would now not boot because the drive and motherboard ID no longer matched for when the password was set.
So, not realising this (because I forgot to tell them and remove it - which I couldn't anyway because of the board fault), they replaced the drive as well.
Result: a new motherboard, drive and lost data.
I was just lucky that it was less than 7 days old and apart from installing a couple of apps I hadn't had much of a chance to fill the drive.
All in all, much easier to remove the password beforehand when cloning or doing a full image backup.