The other day, I was digging through a drawer and I came across a 100GB PATA notebook drive that I had replaced in my personal laptop with a 100GB 7200RPM. I pondered the thought of putting it into an external case so I could do some Ubuntu package deployment testing when I realized it would be really very cool if I could make the drive fit IN the laptop.
So, I pulled the notebook apart and began walking through hacking my spare drive into it.
Here's the laptop before I did any work to it, as you can see it's just a run of the mill Compaq notebook. Single core AMD 3500 socket 939 w/ 2GB of DDR memory and a 100GB 7200 PATA
drive. Once completed this laptop will have 200GB of total storage; 100GB 7200 RPM connected to the primary master, and 100GB 4200RPM connected via USB.I kept track of each screw by storing each type in a small pile which I kept together with scotch tape. I labeled each pile to whatever the screws belonged to like case, display, keyboard, etc. This allowed me to completely disassemble and reassemble the laptop very quickly without error. I was sure to use the utmost caution whenever I was connecting and disconnecting double checking everything before continuing. Once I had the laptop open, I had to select an interface to connect to
. The options were: Primary Slave, Secondary Slave, and USB. I ruled the first two out pretty quickly. While they weren't impossible, they involved significantly more effort as I would have had to de-solder the connections (44 pin header on the primary, and a 50 pin header on the secondary) and solder 44 individual connections in addition for finding a way to re-route the cables so the connections still worked for their native devices. Using the USB bus, I was able to drop the disk inline with the USB port by soldering connections directly to the motherboard. I added a small switch to I could turn the drive off when it wasn't in use to save power. Additionally, I can also use the USB port for other devices while the second hard drive is powered off. On the motherboard I soldered a total of 4 connections to USB (Pinout: 1: VCC, 2: Data+, 3: Data -, 4: Ground). I ran the connection from pin 1 (VCC) to a single pole single throw (SPST) mini-toggle switch which I mounted in an open area on the opposite side of the laptop from the hard drive and then ran the connection back to the USB input on the 2.5" drive adapter. I then connected the rest of the data and ground connections using the bundled USB cable without it's connectors because it's USB 2.0.In order to make the drive fit properly, I needed to cut some of the metal on the right side of the laptop that protruded from the Kensington lock. Using a dremel and metal cutting tip I sliced about 1/2 of the two small sections away which allows me to retain complete functionality of the lock and doubles as a mount for the drive itself. Additionally, I shaved some of the plastic from an unused screw mount which was probably there from supporting an earlier model (there was nothing connected to it). Once I had the metal and plastic trimmed, I mounted the hard drive
into the case and ensured that my newly added cables were not in the way of the DVD sled. Once I had the drive in place, I used a non-conductive heat shield from an old power supply to protect the drive electronics from the top of the DVD (note: the drive only looks upside down, the keyboard is actually on the other side so when complete it is mounted upright). I then began to re-assemble the notebook without bolting anything down to ensure that the computer still booted, and that it did see the drive (success woot!). Once tested, I completely re-assembled the notebook and was pleased to see that 
everything fit perfectly, and worked. If it wasn't for the toggle switch, you wouldn't know that there were two hard drives hacked into the laptop, as it looks just like it did before I started.UPDATE: I found a great little rocker switch to replace the toggle, and I've installed it this morning. (June 28). Pics below.
