SATA and eSATA

In this video from ITFreeTraining I will look at SATA and eSATA. SATA has become the dominant connection used to connect internal storage devices in computers so it is important to know about it.

PATA/SATA
0:11 To understand SATA better, let’s first look what was used before SATA. Parallel AT Attachment or PATA was first developed in 1986. It used a 40-pin ribbon cable that could support two devices on the same cable. The cable transferred 16 bits at a time in parallel. It was powered by the Molex power plug. Traditionally the Molex connectors were white in color. Generally, you will find that power supplies sold on the market today will have a few Molex power connectors.

The cable itself has a maximum length of 18 inches or 457mm. Although not a bad length, in modern computers with large expansion cards and other objects in the way, this can make it difficult to connect devices to the cable. This gets more complex if you want to remove a device from a computer. Due to its short length, you may need to disconnect the cable from the computer or disconnect the cable from another device to remove the device from the computer. This makes it harder to plug in and unplug devices.

The ribbon cable is also quite bulky and thus can block air flow. The PATA cables were the dominant cable until the year 2000 when the SATA cable was released. SATA stands for Serial AT Attachment.

The SATA connection uses a 7-pin data connector and a 15-pin power connector. It increases the length of the cable to 3.3ft or 1 meter. There were a lot of small improvements; the biggest improvement was that SATA supports hot swapping. Hot swapping is being able to plug in an unplug storage devices without having to switch the computer on or off.

Hot swapping requires a few things. First, the computer or the device not being damaged when it is installed. This can occur with electronics when something is first plugged in, as there may be a rush of power to the device. The second thing hot swapping requires is for the device and the operating system to be able to recognize a device was installed or removed. Although hot swapping is officially supported, it sometimes won’t work. For hot swapping to work, it requires the motherboard, BIOS and operating system to support it. You won’t damage anything by plugging it in and giving it a go, and if it fails to work, give the computer a restart and it should detect the device.

Let’s have a closer look at how SATA works.

Data Connector
2:35 The SATA data connector is an L-shaped connector. This prevents it from being plugged in the wrong way. The data connector has seven pins. The data is transmitted using differential signaling. Differential signaling uses two wires to transfer data. This helps reduce noise and data corruption at high speeds – something that is essential when you are using serial communication. The other pins in the cable are ground pins.

Since two pins are used for transmitting data and two for receiving data, this essentially means that SATA has one data channel. When differential signaling is used and there is bi-directional transfer like this, it is often referred to as a lane of data. So essentially SATA supports one lane.

There are other data cables on the market that use more than one lane. This is one of the reasons, which I will cover in more detail later in the video, why it is unlikely in the long term that SATA will continue to be used.

SATA Power Connector
3:36 The SATA drives use a new power connector. Like the data connector, this connector is an L-shaped connector, so you won’t be able to plug it in the wrong way. This power connector has 15 pins. It contains 12 and 5 volt pins that were traditionally provided by the Molex power connector. However, it also adds a 3.3 volt pins.

Since it contains an extra voltage, if an adapter is used to convert Molex to SATA power, it will not include the 3.3 voltage. However, this is generally not a problem because very few storage devices use the 3.3 voltage option.

We know that SATA supports hot swapping, so next I will look at how this is supported, particularly now that we have up to three different voltages on the one power connector.

References
“The Official CompTIA A+ Core Study Guide (Exam 220-1001)” Chapter 3 Lesson 10783-11012
“CompTIA A+ Certification exam guide. Tenth edition” Pages 298-303

Credits

[raybrown]

I'm in my mid 60's now & very keen on learning about modern Technology, especially computers & desktop PC's. Although I still follow many of the other high tech you tube video's, which are v informative but (imo) somewhat biased towards gaming etc. Although V knowledgeable & often quite entertaining (Jayzee etc.) I find them sometimes a bit unclear as all I really want to know are the facts. For that reason I honestly think your videos are the best of the best as they're so well presented, clear & informative. Many Thanks to you & your Team. Regards, Ray.

[tonydarre]

Thank you. I've been waiting to purchase one of these new eSATA drives I have been hearing about for years, and now I am armed with the knowledge to purchase the right one.

[Krashulka]

If I remember rightly, the Amiga Computer used Sata before IBM pc's. I was using sata for my amiga harddrive around the time of the IBM 386 . Cheers

[uvxecqy]

Excellent. Just what I have been looking for. Thanks for your channel!

[hamsalunamustapha]

Thank you very much for making a video like this, because of this you can help more people specially an i.t. beginners with free handouts

[vickytechie]

I like it before watching as I know content is always good.

[mrnone]

Informative from you as usual, thank you.

[Shafkatsharif]

100th comment.
Anyways, this was so informative that I really have no words. Wish you good luck and hope to see more such contents in the future.
I really appreciate how informative and comprehensive this video was. This was my first video of yours. I have immediately liked and subscribed. and I will watch all of videos too!

[Tigs]

I recently purchased a brand new Synology RaidStation NAS box which comes with 8 x 3.5” drive bays. Because I needed more storage, I also purchased a 4 bay expansion box. Imagine my surprise when the main unit connected to the expansion unit using an eSata cable.
To add insult, the cable that came with the unit was defective and I had to buy a replacement.😢

[timjonestek]

Nice bit about NVME vs sata at the end

[vertaniacity]

Nice Video ! Everything I wanted to know about eSATA and More !

[nonoyshowtv]

Hello po host sending my love and support to your house God Bless you po keep safe.

[lightningvini]

i used to have an old Toshiba satellite with an eSATAp connector, only years down the line did i realise that it also supported USB

[vladislavkaras]

Thanks for the great and informative video!

[train]

A most superb video sir, very helpfull indeed, thanku.steve from the uk

[pb]

Hi Austin, thnxs a million for this video. I'm nearing 70yrs and plan on building my first PC. Still in learning phase. Now compiling an URL database with all YTube pcbuild and tech-info video's I can find. This one comes on top. thnxs. Planning my PC: Gigabyte MB550M, CPU 5600X, GPU (like GTX1660), M2SSD, RAM. I want to take from my old PC: DVD/RW 10yrs old, HDD 5 yrs old, SATA SSD 1 yr old. (plan to build PC with only M2 first, than install WIN10 from my WIN-USBflash.) B550M has 4 SATA3 6GB headers. How do I data-connect my 'old' devices? what device in which header? Your answer will be so much appreciated.

[webbophone]

Thank you very much for your helpful videos!

[jmoninonoy]

Hello po host watching sending my love and support to you God Bless you po keep safe.From #Nonoy Show TV

[princedelagawu]

this video is really easy to understand. thanks sir🙏

[brianj]

I would love to have seen where the fire wire for into the scheme of things