eGPU stands for external graphics processing unit. An eGPU is a GPU that is installed outside of a desktop or laptop inside a box similar to a PC tower but far smaller. There are many promising aspects for eGPUs, but do those aspects hold true or fall short compared to their internally wired counterparts? In this article we will explore the benefits and drawbacks of eGPUs and whether or not they’re worth buying in 2019.
How eGPUs Work
eGPUs work by connecting to a desktop or laptop via a Thunderbolt 3 cable which uses a USB-C connector and port. Thunderbolt 3 cables are excellent connectors for external storage or high-resolution display, especially compared to USB 3.0.
However, Thunderbolt 3 has bandwidth limitations that do not allow eGPUs to do what their dedicated internal brethren accomplish. Latency issues abound due to Thunderbolt 3 lacking a connection directly to the CPU, whereas a GPU plugged in directly to a motherboard doesn’t experience these latency issues.
Thunderbolt 3 has a bandwidth speed of 40 Gbps but the extra steps and cable length prevent an eGPU from reaching 40 Gbps speeds. In fact, the theoretical speed of 40 Gbps is cut in half to around 21 Gbps, while a GPU directly connecting to the CPU via the motherboard allows a connection speed of 26 Gbps. An eGPU can render about 70% to 80% its max potential compared to GPUs that are directly wired into a desktop or laptop’s motherboard.
No matter the model of eGPU used, whether that be a GTX 1060 or GTX 960, the processing power of an eGPU can be reduced by as much as 20% of its potential max processing power.
For gaming, having a GPU’s processing potential reduced is simply not an option, especially for players that game competitively on first-person shooters, e.g. Overwatch and Fortnite. For sandbox-based games, an eGPU would be more viable than the former since the need for the lowest latency possible isn’t nearly as crucial as it is in first-person shooters.
For games like Sims 4, Cities Skylines, Planet Coaster and Civilization 6, an eGPU would be usable and bearable. However, an eGPU would not be ideal since the user wouldn’t be getting their money’s worth for how much they spent on the GPU alone. Sandbox games like Civilization 6 and Cities Skylines can end up being more CPU heavy in certain circumstances, especially in the late game of Civilization 6 or when building megacities in Cities Skylines.
Who Would Need an eGPU?
eGPUs work best for graphic designers working on the go or for multiple projects that demand different levels of graphics processing. Some graphic designers may have a need for an eGPU at one point, especially when working with programs that demand massive amounts of graphics processing, e.g. Octane Render. At other points, graphic designers may be working with programs that aren’t graphics heavy, not requiring them to transport an eGPU with them.
Unlike gaming, graphic design work does not require as little latency as possible between the GPU and CPU. An eGPU would allow a graphic designer to work on the go without having to lug around large computer towers, nor sink more than $1000 into an unneeded gaming laptop. However, rendering will still take longer with an eGPU, reducing work output speed.
For casual computer users, an eGPU is a solution to many problems that can occur when using an older computer with an integrated GPU. A common problem with older computers containing an integrated GPU is general slowing in most functions, especially web browsing.
Since web browsing and other casual computer usage doesn’t require nearly as much of bandwidth or low latency to function smoothly, an eGPU would fix many problems that plague older computers. However, the cost for an eGPU box averages around US$200, and a GPU meant for casual use can cost between US$50 to US$100, bringing the total cost to US$250 or more, which isn’t exactly cost effective.
eGPUs are an emerging technology that offer a ton of potential but still need optimization. In order for eGPUs to become truly viable, there will need to be a connector developed that increases bandwidth and lowers latency to the point where there is no difference in performance between an eGPU and a GPU wired into a computer’s motherboard. For now, we recommend holding off on buying an eGPU in 2019 and spending your money on a laptop or desktop that will be worth every dollar.