I've talked about external GPUs quite a bit in the past and even reviewed a couple of them. I'm a big fan of the promise of external GPUs, whether it's for use with a laptop or a mini PC that doesn't need a lot of power all the time. But as much as I like the idea of external GPUs, I have to admit that the concept just doesn't make sense for most people.

You may have been tempted by external GPUs based on some of my previous writings, but if I'm being completely realistic, you probably shouldn't bite the bullet. Here are a few reasons why external GPUs really aren't meant to be for everyone.

4 They add complexity

Another item for your desk setup

First off, it's worth noting that a setup using an external GPU is inherently going to be a bit more complex to manage. Rather than having just a laptop or a desktop, you now have to have space for your laptop, your external GPU, and your peripherals if you choose to use them. If you're playing with a keyboard and mouse, all of these components quickly add up and take up a lot of space on your desk.

Plus, you may need more cables to run it all. Of course, you may need more cables to run it all, too. Maybe you can just connect all your peripherals to your external GPU, which does simplify things, but if you can't, then plugging everything into your laptop every time is a bit of a hassle. Or, say, if you sometimes want to use your monitor without the external GPU, that means swapping the HDMI cable around or having multiple cables connected to your monitor.

It's far from the biggest problem, but if you like a clean setup like I do, an external GPU can sometimes be more of a problem than a solution.

3 Bandwidth limitations

Thunderbolt holds external GPUs back

GPUs are incredibly powerful hardware, but part of the reason they do their job so well is the large bandwidth and low latency they when connected directly to your desktop's motherboard. Modern GPUs use a PCIe 4.0 x16 connection, which means they have a total bi-directional bandwidth of 64GB/s (that's gigabytes, not gigabits).

But the most common standard for external GPUs right now is Thunderbolt 3 or 4, and that protocol only comes with bi-directional bandwidth up to 40Gbps (gigabits), which equates to around 5GB/s. And that's for the entire connection, which includes USB ports and other potential uses for the technology, so the effective bandwidth available to a GPU is even smaller. In my testing, a Thunderbolt/USB4 GPU achieved no more than 2.5GB/s of bandwidth, which is a very far cry from the full potential of a desktop GPU.

Thunderbolt 5 is on the way and promises up to 80Gbps of bi-directional bandwidth, or up to 120Gbps in a single direction. That's similar to another interface used for some eGPUs, OCuLink, and it's a major step up, but it's still far from the full potential that most modern GPUs can offer. A high-end GPU like the GeForce RTX 4090 will be extremely held back when connected externally like this.

2 Laptops are inherently slower

A desktop GPU probably doesn't make the most sense

Even if the Thunderbolt connection was perfect and provided the full bandwidth needed for a GPU to perform its best, a setup with an external GPU likely still isn't the most logical approach. Desktop and laptop components are designed very differently, and hardware designed for desktop PCs is all meant to go together because it's much more powerful.

If you take a desktop GPU and put in an external GPU enclosure to use with a measly laptop processor, you're not going to be making full use of that. In the past, it may have made a bit more sense, but these days, games are pushing the CPU almost as hard as the GPU, so using a laptop processor and a desktop GPU is still going to hold back your performance in some games and workloads.

In most cases, if you want gaming performance in a laptop, it makes more sense to buy a gaming laptop with a dedicated GPU already, and if you want desktop-level performance, you buy a desktop PC with the appropriate components. Mixing and matching is not the best approach.

1 Cost

External GPUs aren't much cheaper in the grand scheme of things

Finally, something else to consider with all of this is the cost of using an external GPU. For starters, an external GPU is going to require a laptop that's already featuring Thunderbolt 4 ports, and that's something you usually see in high-end laptops, so you can expect to spend around $1,000 just to be able to use an external GPU. And if you want something like OCuLink or Thunderbolt 5, well, good luck, because devices leveraging those protocols are very uncommon.

Then there's the eGPU itself. An enclosure alone will probably cost you at least $300, and then you still have to buy the GPU itself, which, depending on the model you choose, is another $300 on top of that for a relatively low-end card. After all, even an RTX 4070 is already in the $500-$600 range. So you're looking to spend at minimum $1,600 for the whole setup, and even if you already have a laptop, an external GPU is still going to be at least $600, but the performance you get won't match what you're paying due to the problems I already mentioned above.

You could buy an integrated eGPU solution that already includes everything, and that will probably lower the cost for the whole package, but it also means you need to buy the whole solution again when you want to upgrade, which makes upgrades more costly than they would be on a desktop PC. No matter how you look at it, the cost of an external GPU set up is always going to be a downside.

External GPUs are cool, but they're a novelty

As much as I love external GPUs, it's clear to me that they're not the ideal approach for someone who wants to get the best gaming experience, overall performance, or bang for the buck. They're aimed at a very specific subset of the market that only wants one PC that can handle gaming and demanding workloads but still be portable when the situation calls for it.

That's not to say this segment of the market doesn't deserve a solution, and I'd say I'm a good fit for this kind of product. But it's clearly not made for everyone, and that's okay. You should always make purchases knowing your needs and what fits them the best, so hopefully this article helps clear some things up.