How To Physically Install A Second Internal Hard Drive

When you find yourself running out of hard drive space, you can either delete something or add some more space. While an external USB hard drive is an easy plug and play option, it’s not really ideal – they take up disk space, possibly an extra power socket, use up a valuable USB port, and are generally slower than internal drives. Let’s take a look today at the more difficult option of adding a second internal drive.
Now would be a great time to download our new guide – Your PC, Inside And Out – to familiarise yourself with the basics of your computer. We’ll be focusing only on the hard drive today, but the guide will give you a great overview on all the random sockets and ports you’ll see on the motherboard once you’ve cracked it open.

Step 1: Identify If You Can Add Another Internal Drive Or Not

Not all computers are built equal, unfortunately. If you have a laptop, or an all-in-one machine where the system internals are hidden behind the monitor – then your only option is to go with a USB drive and you really shouldn’t think about opening it up. If you have a slim desktop then read on, as there is a chance you will have enough room for a second drive. If you have a mid to full size tower, then you should be able to easily add a second drive, or two, or three! Refer to the chart below if you’re unsure.

Step 2: Backup

Although we’re not anticipating any problems, it’s good practice to back up your crucial data before doing any kind of hardware alteration. We’ve covered some great options for backup here, and here in our directory.

Step 3: Open The case

Before going any further, unplug the power from the case and all peripherals.
Most tower cases can have their sides removed with just two screws. You need to remove the side which doesn’t have the motherboard on it, so look at the back of the system, find the USB/mouse ports, and remove the OPPOSITE side.

Step 4: Get Rid Of Any Static Electricity In Your Body

When touching the insides of a computer, technicians use a grounded wrist-band to reduce the risk of shocking any delicate components with the static electricity stored in the human body. For our purposes, touching a radiator will suffice.

Step 5: Find The Hard Drive & Connectors For It

The insides of all computers are quite similar, and you can read the PDF guide for a full breakdown. The hard drive is a fairly sizeable chunk of metal like this:

You should find it sitting in a metal cage of some sort. Check now to see if you have room to fit another one in there. A tower case will normally have space for up to 3 or 4 drives, but a smaller desktop system may have only been designed to take one drive, in which case you’re out of luck and will need to consider either upgrading the one already there, or using a external USB drive instead.

Step 6: Identify If You Have A SATA Or IDE Drive

Look at the following picture and compare it to your drive. If yours is of the type at the top, with a wide ribbon cable – it’s a very old connection type called IDE. Ideally, yours will be SATA. If you do find yourself with an IDE drive, you’re not completely out of luck but I’m afraid it’s out of the scope of this guide. IDE drives are becoming increasingly harder to buy, and it’s a good indication your computer is really getting old.

Check out the things plugged into it. One will be power. There are two possible types of power cables, and you will of course need to find a spare one in your system that you can use. These might be tucked away somewhere, so follow the other power cables carefully and try to find a spare one.

Some hard drives can take either kind of cable, but the SATA type are easier to plug in so I use those if available. If you have a spare power cable but it isn’t SATA, you can still get a second drive but you’ll need to make sure it can accept a MOLEX type power cable, or you can get a MOLEX to SATA adapter for under $10.
Next, follow the SATA data cable (not the power one) to the motherboard, and have a look at where it is plugged in. Different motherboards have different numbers of SATA ports, and older machines may even only have one. Obviously, if you can only find one SATA port, then you can only plug in one SATA drive drive. If you can see some spare sockets, then congratulations – you can now go buy a second drive!

Step 7: Buying A Drive

There is very little between drive manufacturers, and most hard drives that develop a fault do so within the first week of use. On the technical side, you are looking for a “3.5 inch SATA hard drive”, and make sure you pick up another “SATA cable” while you are there – the store clerk should able to help you with this if you can’t find one.

Step 8: Install

Sliding the drive into the cage is the hardest part as sometimes it can be blocked by a large video card or other cables. Identify the cables before you actually go ahead, noting which sides face up (SATA data and power cables all have a little notch on one end which means that inserting it the wrong way around is virtually impossible).
Once seated in the drive cage, use the screws that came with the drive to secure it – you will need to align the holes on the drive with the holes in the cage or tray. Next, find the spare power cables and the SATA cable, and plug those in. Replace the side, and power up the machine.
I’ll be covering the software and configuration side of adding a second drive in my next article – so stay tuned for that. As ever, feel free to ask any questions in the comments and I’ll do my best to answer.