What is Thunderbolt 3? Revolutionary tech for your notebook

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Tech is moving fast! Remember when you were a kid and older people asked you to fix their electronics and computers?

Well, at the current innovation rate of the industry, maybe it is time to befriend the younglings next door, just to be sure we won’t yell at our TVs when the next gen of super high-end thin OLED TVs hits the market!

One of the newest and coolest things that computer industry came out with is the Thunderbolt 3 interface.

What is Thunderbolt 3? In the article below, I’m going to tell you it is, what is the thunderbolt port used for and why it is a gamechanger for laptops.

Regardless if you’re tech-savvy or not,  I promise you’ll understand what can be achieved using this new innovative technology, so please, stick around!

What is a Thunderbolt 3 port

Thunderbolt is a hardware interface developed by Intel. As the name suggests, it is the 3rd generation of this port. It can reach speeds up to 40 Gbit/s.  To put things in perspective, USB 3 bandwidth of 5 Gbit/s. That’s 8 fold increase in speed right there!

Daisy Chain

Daisy chaining is the ability to connect one Thunderbolt device to another device, and that device to another and so on. Thunderbolt supports daisy chaining up to 6 devices.

Even if your notebook has only one Thunderbolt 3 port, it can still connect up to 6 devices by daisy chaining them together. The ability to connect multiple devices to a single port makes Thunderbolt ideal for thin and light laptops.

This allows adding dual monitors, docking stations and external GPUs by plugging in the laptop just one cable that also charges the device. How cool is that?


Although the features we mentioned are pretty cool on themselves, Thunderbolt 3 can also deliver power through the same connection, up to 100Watts.

A regular notebook requires 65W of power. Having the ability to deliver both power and data reduces the number of cables you have to plug into your notebook, removing some of the clutter on the desk and making for some good looking setups.

Two Vs Four PCI-Express Lanes

Thunderbolt 3 comes in two variations, depending on the number of PCI-Express lanes that it uses. It can use 2 lanes or 4 lanes.

Laptops that have more than one Thunderbolt port, use 4 lanes for each. If you plan on squeezing every bit of bandwidth from your Thunderbolt port, make sure to get one with 4 lanes.

This is especially recommended if you intend on hooking an eGPU(external graphics card) to it. The community is still split when it comes to the actual numbers, but the general sentiment is that there is a significant performance difference decrease for the two lanes port.

We’ll address eGPU optimizations later in this post.

USB C vs Thunderbolt 3

Since the 3rd generation, Thunderbolt uses USB-C connector, which can be inserted regardless of its orientation. No more three attempts to connect the regular USB cable! This truly feels like we live in the future!

Thunderbolt 3 and USB-C may share the same connector type, but they’re different technologies. A Thunderbolt port accepts USB-C connection and if a thunderbolt cable is plugged into a USB-C port, it will function as a USB-C connection.

The most important thing to take from this is: make sure that the device you’re planning on purchasing has Thunderbolt 3 and not only USB-C. These two can be easily mistaken and the naming schemes don’t help either.

USB-C is a new design for the familiar Universal Serial Bus interface. It provides a solution to the many USB connector types that clog your drawers only to be used a few times throughout their lifespan: USB A, USB B, micro USB A, micro USB B, etc.

Its purpose is to bring some uniformity across the USB world. With USB-C, devices like computers, laptops, printers, and chargers can share the same connector and cable.  One cable, to rule them all.

Thunderbolt ports usually have a lighting icon near it to differentiate it from a regular USB-C one, as you can see in the picture of my Lenovo Thinkpad T470, which sports 2 PCI-Express lane.

Lenovo T470 2 Lane Thunderbolt 3 Port

What can I use Thunderbolt 3 for?

Having 40Gbit/s with 100W of power opens a lot of cool possibilities. Until it came out, these kind of speeds were only possible by connecting things directly into the motherboard.

Although this technology is very young and it has not yet been adopted by the majority of the laptop industry, there are many game-changing usages. We’re going to explore the most popular ones.

The high bandwidth allows connecting external devices that can turn a regular notebook into so much more.

What devices use Thunderbolt?

The most popular ones are eGPU, external storage devices, dongle adapters, docking stations and pretty much everything you can think of can be made to be used with Thunderbolt 3.

Many manufacturers have embraced it and the docking station community has run rampant with it, each one of them trying to outdo the others with lower prices and better quality and functionality.

This can only be good for the average consumer. Let’s explore some thunderbolt port uses!

External GPU for your Laptop

A decent GPU can transform any laptop with a good processor into a decent gaming machine, but adding a new GPU to your old laptop is either not possible or it’s a real hassle.

At least this was the case until thunderbolt GPU enclosures appeared on the market. Now, you can hook the latest generation desktop graphics card to your notebook and enjoy a great performance boost in your favorite games or reduce the rendering time for your video projects.


Although there is overhead, some of the GPU power is lost, compared to a regular GPU mounted directly into a PCI-Express slot, but the performance is manageable.

Because the GPU delivers the output image back to the laptop to be displayed on the screen, it consumes a lot of the bandwidth of the Thunderbolt port.

The best way of reducing the overhead on the thunderbolt cable is to use an external monitor. In this way, the GPU doesn’t have to also push back to the laptop the display signal, freeing a significant chunk of bandwidth.

If you plan on using your laptop for work or school but would also like to do some gaming while at home, eGPU provide a good solution. If you’re not yet settled on a laptop, make sure to get one with Thunderbolt 3 with 4 PCI-Express lanes as it offers better results.

Yes, two PCI-Express lanes are slower than four. The math checks out.

As with many of the Thunderbolt peripherals, you can also use the GPU enclosure as a docking station and dongle adapters. We’re going to talk more about docking stations later in this post.

Thunderbolt Compatible Monitor

The cool thing about USB-C monitors is that you can use them as a USB docking station and also as a power adapter for your laptop. You can hook up two 4K monitors at 60Hhz. Wow, that’s a lot of pixels going through one tiny cable.

Because of the daisy chaining feature, one of the 4k monitors can be connected to the other one so that, again, only 1 cable is plugged into the laptop.

Monitors come with a lot of regular USB ports. This can be used as a docking station to get access to more ports that may be missing from the ultrabook.

At the moment, the highest charging power that a monitor can provide through Thunderbolt is 65Watts. If you plan on getting a monitor for your laptop, make sure your ultrabook doesn’t need more than that.

As a rule of thumb, the larger the screen size, the more power it needs for itself and the fewer Watts it can deliver through the Thunderbolt cable to charge your notebook.

There are laptops that require less power, for example, my own Lenovo T470 only needs 45Watts. This allows me to use a big 27″ monitor as an external monitor and still get all the juice I need from my laptop without having to plug in in the power adapter like some kind of old-timey person.

Again, double check the power consumption of your laptop the power output of the monitor before coming to a decision, as it can be easily messed up even by pros.

Fast Data Transfer

The high bandwidth of the protocol makes it the best candidate for external data storage. There are already on the market external NVMe drives that can reach speeds up to 2,800MB/s and write speed of 2,300MB/s.

Imagine writing a 40GB BlueRay movie to an external drive in 20 seconds. Madness!

This can make life easier for anyone that works in the video production industry. Having to transfer a large amount of raw footage became an easy task.

Laptop Docking Station

Notebooks that have a Thunderbolt port can be hooked to amazing docking stations.  Connect all your USB devices, keyboard, speakers to the docking station via the Thunderbolt 3 cable.

Lenovo has a docking station that has an Nvidia GTX 1050  GPU included for a  boost in performance. It is way smaller than an external GPU enclosure and it looks great on the desk.

As we said earlier, a thunderbolt monitor or external GPU enclosure can be used as docking stations because they come with various ports and the ability to daisy chain other Thunderbolt devices.

That being said, because of the low prices of docking stations compared to monitors and eGPUs, they are still a viable solution to use your older devices and hook them all up with one cable to your notebook.

From laptop to desktop with 1 cable

My favorite thing about Thunderbolt is the ability to use my thin and light ultrabook to create a desktop setup with dual monitors, keyboard, mouse, and speakers.

I can connect my laptop to the mentioned setup using only one Thunderbolt cable that also charges my device. It takes one second to hook the laptop up to the setup and one second to remove it and place it my laptop backpack.

Because Thunderbolt also provides power, I can keep my laptop’s power brick in the backpack at all times. Removing it from the backpack, plugging it in a socket every time you get home isn’t that much of a hassle, but if I can live my life without having to do it, I’ll definitely prefer not to do it every time I come back from school.

This is awesome for someone anyone that likes to pick up their laptop and move to the couch, kitchen or outside, but they also like having a high-resolution setup with plenty of screen real-estate.

You may say to yourself: “Why not just get a mid-range desktop as a second computer to use while you’re at home?” Well, that is a valid point. But I hate having my work on two devices that are not synched, having to look for files on both machines and having to maintain two computers.

As long as you’re not doing very CPU & GPU intensive work, this kind of Thunderbolt 3 Laptop + Docking station gets the job done while keeping your desk looking clean with few cables.

Dongle King

Having a Thunderbolt port and the right dongle can replace the need for any other ports. Apple has already started removing many of its notebook’s connectivity and handing out Thunderbolt dongles in place.

This allows them to make their devices thinner and lighter, but people still need to connect the old USB and ethernet cables. Equipping the laptop with a couple of Thunderbolt ports and adding the right dongles.

The power users may not like this move, but the overall industry doesn’t seem to mind that much. I guess you need to remove the old in order to embrace the new.

Thunderbolt to HDMI and Thunderbolt to  Ethernet 10gbs adapters became very popular thanks to Apple.


Although it has been released since 2015, it is starting to become popular now as more devices started taking advantage of the massive bandwidth it provides. I’m very excited about this technology. It opens a new era for mobility and performance.

Take your work anywhere you need, but while you’re at home, hook your ultrabook to powerful external components that transform it into a machine that can go head to head with desktop computers.

The price can be a little spicy at the moment for the Thunderbolt devices, but as the market goes and more of the big manufacturers come out with products, it will certainly go down.

Apple has embraced Thunderbolt 3 and it partnered with LG to deliver high-resolution monitors capable of also charging their MacBooks.

Microsoft Surface, on the other hand, didn’t include a Thunderbolt port on their devices, but I’m sure this thing will change with future iterations of the tablet.

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