Note: Hitman 3 data was excluded from the following charts as we were only able to test the game when using an external monitor.
1080p Average – When Using the Laptop Display
1080p Average – When Using the External Display
Grouping both 1080p charts together, if for whatever reason you cannot use an eGPU with an external monitor, a decent level of performance is still on offer from the four GPUs tested. However, we can clearly see little benefit to the using the RTX 3070 over a RTX 3060 Ti, and I’d say the same for the RTX 3090 instead of an RTX 3080 – Nvidia's flagship GPU is 7% faster, but that’s just a difference of 4FPS on average.
Now, if you can use an external monitor, you will unlock 10-12% extra performance from your GPU of choice, simply because the Thunderbolt 3 cable isn’t having to first send data from the laptop, to the GPU and back again – the display output is now being handled externally via a HDMI or DisplayPort cable. That said, actual scaling between these GPUs is similar. The RTX 3090 is still 7% faster than the RTX 3080, while the RTX 3080 is still 15% faster than the RTX 3070. The smallest gap between all four GPUs is between the RTX 3070 and RTX 3060 Ti, as we see just a 5% margin between those two GPUs.
1440p Average – When Using the External Display
If you want to use an external monitor for eGPU gaming at 1440p, once more the biggest gap between the GPUs is with the RTX 3070 and RTX 3080, with the latter of the two proving 20% faster on average. The RTX 3090 is still just 7% faster than the RTX 3080, while the RTX 3070 is 6% faster than the 3060 Ti. That means we are seeing a difference between the four GPUs on test, but the margins aren't as large as you'd expect on a desktop.
2160p (4K) Average – When Using the External Display
As for 4K, you can just about get away with eGPU gaming at this resolution if you get an RTX 3080 or RTX 3090, but I wouldn’t say it is ideal. Interestingly, the gap between those two cards works out as a 9% margin in favour of the RTX 3090, compared to a 14% difference when we tested both GPUs on the desktop. Clearly the RTX 3090 is unable stretch its legs as much as it would like to, when used in an eGPU.