Unlimited POWER!! Ultrabook and an eGPU?
Unlike Senator Palpatine, I prefer portability over power, could never convince myself that a powerful laptops general weight and unwieldiness was worth it, that said, who doesn't want more power!
Then eGPU's came around, an enclosure that houses your graphics processing unit, and connects to your laptop over USB-C (Thunderbolt 3), could this be the setup of my dreams? I took the plunge and bought the following:
Razer Blade Stealth 2019 (GTX)
Razer Core X Chroma (the GPU housing)
MSI Geforce 2070 super
The first thing to note, TURN OFF ADVANCED POWER SETTINGS FOR PCI EXPRESS (aka Link State Power Management).
This little bugger caused me a few hours of wasted energy and effort, removing, re-adding and rebuilding my system due to severe reliability issues when using an eGPU, to the point i almost sent the whole kit back.
If you're using an eGPU and your system is freezing regularly then this is most likely your cause. Once turned off, solid as a rock.
Performance-wise this setup gives me all the power and flexibility i need in a laptop system, portability when working away from the office and extra power when sat in the office. But what does that power bump translate to? Was it worth the eGPU outlay?
To test I used 3DMark and the Time Spy benchmark test, side by side performance results with and without eGPU below:
As you can see, a pretty significant jump in performance between the 2 results.
But let's be honest, the performance was always going to be significantly better when running on the eGPU.
But is it worth it?
I'd say yes but with several caveats, if you do not need portability this is a pretty inefficient way to create a powerful system and you may be better off with a larger 15" to 17" powerhouse laptop or a dedicated desktop.
This is due mostly to the loss of performance you receive when running a GPU over USB-C Thunderbolt 3 (the connectivity used to access the eGPU). If you were to use the same graphics card installed in a desktop using PCIe you would on average gain around 20% better performance over the eGPU setup, this makes sense as you're restricted to a maximum bandwidth of 32Gbps over Thunderbolt 3 vs PCIe's 126Gbps.
Personally I still think this is a viable solution for creators and casual gamers, that also want flexibility and portability with their workstation. It offers a good compromise.
Finally - some important information regards eGPU capable laptops
Not all Thunderbolt 3 ports are made equal, some have more lanes (bandwidth) available so will enable a better experience over the USB-C Thunderbolt 3 port, there's a great article here that can help you chose the best options currently available.