2018 14" Lenovo ThinkPad X1 Carbon 6th Gen [8th,4C,U] + GTX Titan @ 32Gbps-TB3 (...
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At first I was aiming for ADT-Link R43SG-TB3 because of the price. Besides, I'm quite a handy man and this could be a very nice project.

But, ADT-link TB3 is ~$160 + decent power supply ~$100 = I would have spent some $260 for (hopefully) working setup without any kind of enclosure, let alone additional USB or RJ-45 ports.

Used Core X (not Chroma) on Ebay are about 230-270$, so this didn't seem worth an effort building it myself.

Finally I managed to find and buy used Chroma version in top condition at this price tag.


System specs:


eGPU hardware:


Hardware pictures:


Installation steps:

  1. Installed GPU into an enclosure, connected cables, switched on eGPU.
  2. Laptop started charging, enclosure LEDs lit up, but nothing else happened on PC side.
  3. Followed this Lenovo support article, double checked versions and reinstalled Thunderbolt software.
  4. Still nothing happens, Thunderbolt software still showing no connected device
  5. Found mention about Thunderbolt security setting in BIOS and set this.
  6. Razer device detected, GPU detected, installed Nvidia driver, everything worked from now on. More or less.


Next steps:

After each reboot Action Center notification popped up, stating "Device was approved during boot but is not part of the current Approved Devices list."

Replaced Thunderbolt Software by Thunderbolt Control Center, which allowed me to approve Razer device and set BIOS Thunderbolt security to this.

At first I was quite concerned about particular GPU model support, since Razer website states distinct set of GPUs as supported, while saying nothing about others. Fortunately found that my both cards (GTX Titan and GTX Titan Black) work just fine and even tried a small GTX 710 (which is not listed as supported) and it worked as well. 

My idea is, that Razer enclosure is just a generic PCIe extension, so there might be no reason to support one card, but not the other. Not really sure if this is true though.



Unigine superposition benchmark (1080p medium, internal display): 7166 (compare to 812 points without eGPU).

Desktop PC (i7 9700KF/16GB RAM/1TB SSD) with the same card connected internally made a score of about 7400, so the performance drop is really minimal.

Unfortunately desktop PC lacks TB3 port, otherwise it would be interesting to compare results of the same GPU connected internally and externally.



I was really excited how big difference eGPU made here and how low was the lost of performance compared to desktop PC. After some tests I found some space for improvement though:

  • at some point Superposition benchmark result dropped to about 4500 (30% decrease). I suspect some thermal issue and performance throttling on the laptop side, but can't confirm that right now. Thinkpad got quite hot on the underside, so I let it calm down for 30 minutes and test results returned to previous values
  • I went Core X Chroma way not because it's fancy RGB light, but because of USB and ethernet ports on the back. RJ-45 not tested, but wired mouse connected to the enclosure was very laggy every 5-10 seconds, even on plain Windows desktop (no game or benchmark running). This would ruin my idea about one cable laptop docking. Then I realized, that the mouse was connected to USB hub, which was connected to Chroma. With direct connection to the enclosure the problem seems to be solved. No extensive testing or long term usage though.
  • The setup is not really hot plug. At least not every time. But it might be due to my incorrect usage (might need to stop applications using the GPU first?), will have to do more tests. The fact is that from time to time reboot was needed for GPU to be detected correctly. Also eGPU connected mouse stopped working at some point and needed a reboot.

These drawbacks are rather minor, overall experience is very good for the moment.




This topic was modified 1 month ago
2018 14" Lenovo ThinkPad X1 Carbon 6th Gen [8th,4C,U] + GTX Titan @ 32Gbps-TB3 (Razer Core X Chroma) + Win10 [build link]  

Boltoway and nando4 liked