HOW TO replace DVD Rom with Internal 3.5" Hard drive
Most of this is probably posted in various posts from around the internet. Wanted to try and combine it all into one post. I installed a 2TB 3.5" Hard Drive in my Falcon a couple of years ago. The Falcon 1022'd on me, so I decided to RGH my Slim corona and put the hard drive in there. I know that using a 2.5" drive would be easier, but once my consoles are hacked I never use the DVD-ROM anyway, unless I need to rip a copy of something using FSD3. So I choose to use a larger capacity and less expensive 3.5" drive.
In this post I'll cover what I did with the Falcon, and then show how I mounted in my my MW3 Slim. Numbers in the text correspond with picture numbers.
PHAT
1. I dont have any pictures of mounting the hard drive inside the DVD ROM chassis. I did this awhile ago ad didnt take pix. Basically, you pick a DVD ROM to gut. Remove everything you need from the inside so that the hard drive fits in there. Make sure you keep the sliders and front plastic piece together so you can glue them in, so that the front Xbox Bezel can still be attached to the front of the drive, making it line up properly. Drill holes in the metal case to mount the hard drive. Make sure you have holes cut in there so that the data and power cables can get to the hard drive.
Some of the following pix should help you figure this out.

2. A picture of the 4 main things that need to be changed/modded. You can see the hard drive mounted inside the drive through the hole where the DVD magnetic holder was. The hard drive power cable I made from the stock dvd power cable and a sata power extension cable, soldered together. The slotted fan housing, and the motherboard with hard wired sata data cable. Yes, the cable was soldered and heat shrinked, I put e-tape over it to keep it together.
I made the power cable by soldering the 3 grounds from the DVD cable (pins 7,9,11) together to the 2 grounds on the sata cable, 5 wires, one solder joint. The one 5v wire from the DVD power (pin 5) to the red wire on the sata cable. Finally the two 12v wires from the DVD cable (pins 10 and 12), to the yellow sata power cable. The other wires on the DVD power cable can go away.

3. A picture of the hard drive in the chassis. You get the general idea of what to do. Everyone has their own way to mounting the drive. Mine was a little dirty, but with the covers on, you can't see a thing.

4. Another view of the hard drive and the slotted fan cover.

5. A better view of the fan cover. I had to cut the slot because the cables didnt clear the cover. I probably could have cover up with a better way to mount the drive to move the connectors farther away from the fan cover, but this is what I ended up with. Didnt effect chip temps at all.

6. I took a sata extension cable and cut one end off. I soldered the cable directly to the motherboard. You might also be able to take a hard drive chassis and use the plug in cable, but I like
this method. Be sure to match wires and grounds. It's 7 wires that need to be soldered. Keep in mind, most people who have soldered an extension cable like this can no longer use the built in hard drive connector, even with the 3.5" drive disconnected. Most people assume its the extra interference. Make sure you have the proper length set before you cut anything. It takes a hard turn at the fan area. As long as its in the right spot, it wont effect the fan performance at all.

7. Mounted in the chassis. Gives you a good idea where the sata data cable goes. Yes, the extra 40mm fan on the heatsink helps, wired directly to power supply 12v. Drops temps in CoD about 6-7 degrees Celcius. The tape on the CPU heatsink helps channel the air over more of the fins and concentrates some of the flow right at the tube.

8. Give you an idea of where things land once its plugged in.

9. The way the cables mounted inside the hole in the fan cover I actually had to slide them together before dropping them into the chassis.

10. Everything mounted inside the chassis.

11. Closeup of the cables coming out of the fan cover.
As I said earlier, you can probably come up with a better solution for mounting. Save some time and bother dealing with making room for extra cables. If I left anything out of this part or you want more clarification, let me know, and I'll add it to the post.
............ next up, Slim install.............
Most of this is probably posted in various posts from around the internet. Wanted to try and combine it all into one post. I installed a 2TB 3.5" Hard Drive in my Falcon a couple of years ago. The Falcon 1022'd on me, so I decided to RGH my Slim corona and put the hard drive in there. I know that using a 2.5" drive would be easier, but once my consoles are hacked I never use the DVD-ROM anyway, unless I need to rip a copy of something using FSD3. So I choose to use a larger capacity and less expensive 3.5" drive.
In this post I'll cover what I did with the Falcon, and then show how I mounted in my my MW3 Slim. Numbers in the text correspond with picture numbers.
PHAT
1. I dont have any pictures of mounting the hard drive inside the DVD ROM chassis. I did this awhile ago ad didnt take pix. Basically, you pick a DVD ROM to gut. Remove everything you need from the inside so that the hard drive fits in there. Make sure you keep the sliders and front plastic piece together so you can glue them in, so that the front Xbox Bezel can still be attached to the front of the drive, making it line up properly. Drill holes in the metal case to mount the hard drive. Make sure you have holes cut in there so that the data and power cables can get to the hard drive.
Some of the following pix should help you figure this out.

2. A picture of the 4 main things that need to be changed/modded. You can see the hard drive mounted inside the drive through the hole where the DVD magnetic holder was. The hard drive power cable I made from the stock dvd power cable and a sata power extension cable, soldered together. The slotted fan housing, and the motherboard with hard wired sata data cable. Yes, the cable was soldered and heat shrinked, I put e-tape over it to keep it together.
I made the power cable by soldering the 3 grounds from the DVD cable (pins 7,9,11) together to the 2 grounds on the sata cable, 5 wires, one solder joint. The one 5v wire from the DVD power (pin 5) to the red wire on the sata cable. Finally the two 12v wires from the DVD cable (pins 10 and 12), to the yellow sata power cable. The other wires on the DVD power cable can go away.

3. A picture of the hard drive in the chassis. You get the general idea of what to do. Everyone has their own way to mounting the drive. Mine was a little dirty, but with the covers on, you can't see a thing.

4. Another view of the hard drive and the slotted fan cover.

5. A better view of the fan cover. I had to cut the slot because the cables didnt clear the cover. I probably could have cover up with a better way to mount the drive to move the connectors farther away from the fan cover, but this is what I ended up with. Didnt effect chip temps at all.

6. I took a sata extension cable and cut one end off. I soldered the cable directly to the motherboard. You might also be able to take a hard drive chassis and use the plug in cable, but I like
this method. Be sure to match wires and grounds. It's 7 wires that need to be soldered. Keep in mind, most people who have soldered an extension cable like this can no longer use the built in hard drive connector, even with the 3.5" drive disconnected. Most people assume its the extra interference. Make sure you have the proper length set before you cut anything. It takes a hard turn at the fan area. As long as its in the right spot, it wont effect the fan performance at all.

7. Mounted in the chassis. Gives you a good idea where the sata data cable goes. Yes, the extra 40mm fan on the heatsink helps, wired directly to power supply 12v. Drops temps in CoD about 6-7 degrees Celcius. The tape on the CPU heatsink helps channel the air over more of the fins and concentrates some of the flow right at the tube.

8. Give you an idea of where things land once its plugged in.

9. The way the cables mounted inside the hole in the fan cover I actually had to slide them together before dropping them into the chassis.

10. Everything mounted inside the chassis.

11. Closeup of the cables coming out of the fan cover.
As I said earlier, you can probably come up with a better solution for mounting. Save some time and bother dealing with making room for extra cables. If I left anything out of this part or you want more clarification, let me know, and I'll add it to the post.
............ next up, Slim install.............