eGPUs can definitely improve performance. The greatest limiter here is the ports. If you can go into "About Computer" and find the exact model number of your laptop that would be ideal. That would enable me to Google the manufacturer's page to find the OEM spec sheet so that I can try to learn what the
exact specification of your fastest port is. This would give a better indication of how wise this might be for you. If you only have USB 2.0 ports don't waste the money.
GPUs go into the PCIe 3.0 x16 slot in your motherboard specifically because that slot supports the highest bandwidth of information exchange with the CPU and the memory. These components all communicate at vastly greater speeds than is required for the information they ultimately spit out to your storage or display. In fact, even for the latest m.2 SSDs, which are much slower, this has become an issue. This is why Sony decided not to support allowing true next gen PS5 games to be played from external storage (only PS4 games). They knew consumers would buy the cheapest external storage they could find, and they knew this might cause performance issues at some point in the future-- possibly very long load times. Then that consumer would stomp and vent about how terrible the PS5 is. Better to protect ignorant consumers from themselves: it's the console model.
Transmission Speed Ceilings
- 3 Gb/s = SATA II (<----- PS4's internal drive standard)
- 6 Gb/s = SATA III (<---- PS4 Pro's internal drive standard)
- 0.48 Gb/s = USB 2.0
- 5 Gb/s = USB 3.0 (<--- PS4's external ports)
- 5 Gb/s = USB 3.1 Gen 1 (<---- PS4 Pro's external ports)
- 10 Gb/s = USB 3.1 Gen 2 (<-- PS5's external ports)
- 5 Gb/s = USB 3.2 Gen 1(×1)
- 10 Gb/s = USB 3.2 Gen 1(×2)
- 10 Gb/s = USB 3.2 Gen 2(×1)
- 20 Gb/s = USB 3.2 Gen 2(×2)
- 10 Gb/s = Thunderbolt 1
- 20 Gb/s = Thunderbolt 2
- 40 Gb/s = Thunderbolt 3
Let's say you have a USB 3.1 Gen 2 port like the PS5. Runs at 10 Gb/s. In comparison, a PCIe 3.0 x16 slot runs at 126 Gb/s. Now, that is
way more than any current GPUs require, even the mighty RTX Titan, but that PS5's USB port is still ~50% slower than a PCIe 2.0 x 4 or PCIe 3.0 x 1 slot. At those speeds I believe the GTX 1660 Ti will be bottlenecked significantly.
That's why these eGPUs were more interesting 8-10 years ago when the USB 3.0 and 3.1 ports were freshly out on the cutting edge laptops. The GPUs at the time were snails compared to today. The ports weren't that limiting.