Hello guys and gals.
It's my first post and I just wanted to say thank you all for the collaboration and development of this site and its community.
I decided to try my luck with adding external GPU to my Y540 trough m.2 nvme port with R43SG. The good thing is that everything works out of the box. The egpu Vega 56 was detected and installed without any issue. My both egpu and dedicted 1660ti GPU work along wihitout any errors. The only problem is that egpu is using only part of aviable bandwidth. After digging I came up with this:
In document Lenovo Legion Y540-17IRH Platform Specifications it's stated that
M.2 2242 SSD / PCIe NVMe, PCIe 3.0 x 2, 16Gb/s
M.2 2280 SSD / PCIe NVMe, PCIe 3.0 x 4, 32Gb/s
If I got it right, my R43SG is detected as 2242 ssd not as 2280 ssd. Here is where I need your help. How to achieve 32Gb/s with egpu trough m.2 port in Y540?
Things to consider:
Secure boot on or off
UEFI or Legacy
BIOS downgrade (to a specific version)
Firmware
Hotswap (but it should work as the card is detected and installed without any errors)
Changing the jumper or switches configuration on R34SG
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
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How about submitting a build guide so we know what you are doing and have performance measures?
eGPU Setup 1.35 • eGPU Port Bandwidth Reference Table
2015 15" Dell Precision 7510 (Q M1000M) [6th,4C,H] + GTX 1080 Ti @32Gbps-M2 (ADT-Link R43SG) + Win10 1803 [build link]
Ok. So I need 5 posts to be able to attach a picture. I hope you don't mind if I spam just a little ? 
After digging even more with HWiNFO I found that my m.2 port is running at 4x speed
The weird thing is that this port is not hot-plug capable
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
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