How Many SATA Cables Do I Need?

SATA cables are a necessary component to any computer system. They carry data from the motherboard to your hard drive, optical drives, and other components. The data transfer rate of SATA is 3 Gb/s, which makes it slower than the PATA (IDE) speeds of 16 Mbps. Many motherboards support both types, however.

The number of SATA cables you need will depend on how many devices you want to connect via the SATA port. For each device, you must have a cable connecting it to your motherboard. If your computer has four drives and five slots for drives on the motherboard, but only one connector on the motherboard itself, then you will need three or four SATA cables (depending on what drive positions are available), plus one more cable that connects from another slot on your motherboard back to an empty position on your case for future expansion.

What are SATA cables and what do they do?

What is a SATA cable?

SATA cables are the data-transfer cables that send signals from your hard drive to the motherboard. Without a SATA cable, your computer will not recognize a hard drive and you will not be able to access any of its content. The SATA standard was introduced in 2003 as a replacement for the older PATA (Parallel ATA) standard which had been used since 1986.

The original SATA transfer rate was 1.5 Gb/s, however this has been increased in modern systems to 3 Gb/s. This is still slower than most internal drives can handle, though all external drives use this speed by default. Modern motherboards include several ports for SATA connections, with each port generally being capable of transferring data at up to 3 Gb/s. A computer case will usually have at least one additional external port, which is where many people connect their optical drive(s).

Additionally, some motherboards support SATA RAID (Redundant Array of Independent Disks) and may require special cabling for this purpose. When planning your system build, you should consider how many devices you plan to connect via SATA and ensure the motherboard has enough ports as well as leave room for expansion.

SATA cables are only capable of transferring data relatively slower than USB 3.0, however they use less power and can be daisy chained together for more storage locations on a single cable run. If you’re using its maximum allowable transfer rate of roughly 183 MB/s, then you’d be using roughly 6.3 watts of power per cable or 42.2 watts total for all 6 SATA cables (plus motherboard). Assuming an average price of $1/foot, you’re looking at $6 for 6 feet worth.

If you’re using USB 3.0, then the maximum data transfer speed is 5 Gb/s which would cost about 8.5 watts or around $4 per cable for 6 feet worth. With the additional 30 watts of power usage, this means that adding an external 3 TB HDD would cause your system to draw 46.2 watts vs 42.2 watts without any external drives and with SATA instead of USB 3.0 and these values don’t include motherboard usage either.

However, keep in mind that everything transfers faster over USB 3.0 than it does over SATA and that’s simply due to how much faster USB can be sometimes even if you have two devices that will run at exactly the same speeds across both interfaces such as 2 3 TB hard drives. SATA is a more efficient standard in terms of power usage and can daisy chain together longer distances than USB 3.0 can, though it’s also slower when saturating the link due to its lower bandwidth capabilities.

How many SATA cables will I need for my computer setup?

The number of SATA cables you need will depend on how many devices you want to attach. Most motherboards have two or more SATA connectors on the motherboard itself, with each connector being capable of handling up to 6 Gb/s worth of transfer speed.

If your computer has four drives and five slots for drives on the motherboard, then you would only need three SATA cables (plus one more that connects from another slot on your motherboard back to an empty position on your case for future expansion). If all four drives are 3 TB hard drives running at roughly 183 MB/s over SATA, then this would be 42.2 watts x 4 = 169.8 watts used vs ~153-159 watts if using USB 3.0 instead depending on the exact USB 3.0 controller used with a theoretical transfer speed of 10 Gb/s per port x 4 ports for 40 Gb/s total.

To answer the original question, you’d need three SATA cables from the case to your motherboard and one more from another empty connector on your motherboard back to an empty slot in your case if it has one. If not, then you would likely want at least two 5-15 watt fans in your case so that air can circulate efficiently or a fan controller that supports lower power usage fans is another alternative. I hope this helped!

What are the benefits of using a SATA cable versus other types of cabling?

As mentioned above, SATA cables are capable of transferring data at roughly 3 Gb/s which is much faster than USB 2.0’s 60-450 Mb/s range or the slower USB 1.x standard found on some older systems. If you have multiple devices attached to your computer, then SATA will daisy chain them all together using a single cable instead of requiring one connection per device like with other types of cabling such as Firewire 400, Firewire 800, USB 2.0, etc. Another benefit that people often take advantage of is being able to use SATA II or even SATA III hard drives that can transfer data much faster than what an old 486 CPU was really capable of without special tricks (i.e. software RAID).

How long should a SATA cable be to transfer data effectively?

The length of your SATA cable does matter somewhat because to transfer max throughput requires running at roughly 3 Gb/s per second which is about 12 inches or roughly .3 meters worth. To have maximum power efficiency, you would want to keep any cables as short as possible so that there is less voltage drop across the cabling itself due to the lower current capacity present. If you’re transferring large amounts of data continuously, then shorter cables will mean less heat generated by the drive also since it takes more power to run faster. If you have an extra-long SATA cable however, then this can actually reduce heat output some by allowing for better airflow and reduced resistance per length of cabling. This is why there are special SATA cables that are extra long in certain cases with locking mechanisms to keep them attached when they’re not being used.

How can I tell what type of cable I need for my computer?

If you already have all of your drives attached and working, then the easiest way would be to turn on your computer and look at the drive names or numbers (i.e. 1, 2, 3) which should appear under My Computer if Windows detected the drives properly – otherwise known as Dynamic Disk Mode where each disk is seen by Windows individually without any letters associated with it. If this doesn’t appear, then you will likely need to go into your system’s BIOS settings page to change some of the settings in order to tell Windows how your drives are currently attached. If you have four SATA hard drives, then this means that you are using hardware RAID or multiple disks with no drive letter under Windows which requires special cabling depending on the motherboard used. To check if your motherboard uses chipset-based RAID instead which can be configured through your BIOS settings without needing special cabling, consult the manual for your motherboard or look at the model number on the box of your computer in some cases.

If you have two hard drives and do not know how they are attached yet, then I would recommend buying a cable with locking mechanisms so it cannot accidentally pop out when being moved around – otherwise known as “sliplocks” or “screw locks” depending on the type of cable. On my computer, I use two different types since one is short and the other is only used to transfer data with high performance applications which is why they both look very similar but are slightly different – just look at them closely to figure out which ones you need.

Tips on how to properly install a new set of SATA Cables

There are usually two sets of cables for each type which you can buy so that you have an extra set to work with or keep as spares. Since SATA II is backwards compatible with older SATA standards, then one cable will fit the other just fine if your drive requires a longer cable than what came with it. However, there might be a special model number printed on the side which you should match up instead of using any old cable since not all of them support certain features. The following example shows how I would attach my drives together in this manner:

1. Install the two hard drives next to each other and connect them to your motherboard.

2. Attach one end of a standard SATA cable into your first drive and attach both ends of a special SATA II (i.e. 3 Gb/s) cable into the SATA port closest to where you installed that drive since it will support faster speeds than SATA I (i.e. 1.5 Gb/s).

3. Connect the opposite end of the SATA II cabling into your second hard drive following the same instructions as above – make sure they are facing away from each other if you want maximum airflow without interference which would slow them down some due to operating temperatures being increased by much more than necessary.

4. Connect one end of a standard SATA cable into your second hard drive and the opposite end to the next available port on your motherboard.

5. To power up your system, you would need to attach both ends of either a special SATA II (i.e. 3 Gb/s) or a standard SATA cable depending on what type of motherboard you have to the power supply unit (PSU). The reason for this is because if there were only one set of cables in use, then it uses up both cabling slots which results in reduced speeds since one port will not be able to operate at full speed due to only having two lanes instead of four – something that can cause major issues with data transfers if this becomes an issue after installing an HDD from an external enclosure into your computer.


For a SATA cable, make sure to be aware of the number and type of connectors. For instance, if your motherboard only has two SATA ports but there is more than one device that needs power, you will need an adapter or additional cables. If you have any questions about how many cables you should order or what types of connections might work best for your system configuration, feel free to contact us! Our team can help identify which products would be suited for your specific situation and get them delivered right away so that you don’t miss a beat in business while waiting on parts from other suppliers.