Dell Alienware M18x (Early 2011) - Manual (Page 25)

8. Remove the four screws that secure the primary hard drive (HDD 0) and lift the hard drive out of the hard-drive bracket.
9. Remove the four screws that secure the secondary hard drive (HDD 1) and slide the hard drive out of the hard-drive bracket.
Replacing the Hard Drive(s)
1. Follow the instructions in Before You Begin .
2. Remove the new drive(s) from its packaging.
Save the original packaging for storing or shipping the hard drive(s).
3. Place the primary hard drive (HDD0) in the hard-drive bracket.
4. If applicable, slide the secondary hard drive into the hard-drive bracket.
5. Replace the four screws that secure the primary hard drive (HDD 0).
6. If applicable, replace the four screws that secure the secondary hard drive (HDD 1) to the hard-drive bracket.
7. Connect the interposer to the hard drives.
8. Place the hard-drive assembly in the computer base.
9. Tighten the four captive screws that secure the hard-drive assembly to the computer base.
1 secondary hard drive (HDD 1) 2 interposer
3 primary hard drive (HDD 0)
1 hard-drive bracket 2 secondary hard drive (HDD 1)
3 screws (8) 4 primary hard drive (HDD 0)
CAUTION: When the hard drive is not in the computer, store it in protective antistatic packaging (see "Protecting Against Electrostatic Discharge"
in the safety instructions that shipped with your computer).