2019 15" Lenovo Yoga C940 (GTX1650) [9th,6C,H] + RTX 2070 Super @ 32Gbps-TB3 (Razer Core X Chroma) + Win10 [phila-delphia]  

@phila-delphia, Have you checked the PCH and its temps during gameplay? If it gets close to 80 degress Celsius the Thunderbolt 3 connection through here may get throttled. I found a motherboard photo on notebookcheck that shows an uncooled PCH chip.

Last but not least is the incredible insights @nando4 shared in one of his builds. He mentioned the BIOS optimization for Thunderbolt 3 connection is very lacking on H-CPU systems (except the 15" MacBook Pro). I don't know how feasible it is to produce a patch.

@itsage, Thank you for bothering to help me and thank you for the insight shared. The PCH chip indeed is uncooled - I will give it a look after I return home end of the week and see if there is something I can do about it! I will also read nando4s article!

Thx again for yout help! I will report back!

All the best!

phil

@itsage, I had chance to check the PCH temperature. It will hover at 57-61°C when the TB3 is under gaming load... So that`s not the issue. I suspect the bad 9750h Bios nando mentioned in his build. Still I thank you very much!

All the best!

phil

@phila-delphia I've been considering using the Core X Chroma for a one-plug solution with a Lenovo laptop, but I've heard mixed reviews on its functionality with USB peripherals. Personally I would probably only use keyboard/mouse/mic, but it looks like you're pushing it to the limit. How has your experience been, and could you describe your peripheral setup?

@oversizedmattress, Pushing it to the limit is right... The limit was reached, when I attached an USB splitter to one of the Chromas USB Ports 😉

Right now I use the Chroma with

- Mouse (wireless dongle)

- Keyboard (wireless dongle) -> both of which must not be plugged into one USB port (via said splitter) to avoid interference.

- 1 TB SSD

- 1 RAID ENCLOSURE

- LAN

- HDMI -> LED Beamer

- DP -> Monitor

Everything works like a charm (besides the fact that the 8th/9th gen BIOS issue nando observed and described somewhat hampers gaming performance)

All the best to you!

phila

@phila-delphia Whelp, that seals the deal for me then, that’s incredible! All I need to hope for is half that level of connectivity and I’ll be set

Ps. You probably already know this, but from what I’ve heard hooking up that many peripherals (especially the storage) via the Chroma can take up a lot of your Thunderbolt bandwidth. Have you tried running performance tests with less attached?

@oversizedmattress, yes I did test the performance but the effect is neglectable imho as long as you do not try to run mous and keyboard dongle OR 2 ssd through one Croma USB port like I did

Saying this I have to damit, that I am not the kind of guy that copys millions of lifes while downloading hundreds of GB plus trying to game at the same time...

What hampers performance most are:

- the limitations that I described here ->  https://egpu.io/forums/postid/74218/ (apparently due to 8th/9th gon BIOS)

- the bandwidth limitations TB3 suffers from small block transfer sizes (application dependand)

Both is covered in this exelent thread @nando posted some time ago: https://egpu.io/forums/postid/72088/

Hope all will work out well for you!

All the best!

phila

Posted by: @phila-delphia

- the bandwidth limitations TB3 suffers from small block transfer sizes (application dependand)

This may be illustrated by the benchmarks from @itsage comparing Thunderbolt to PCIe.
https://egpu.io/forums/thunderbolt-enclosures/a-call-for-measurements-isolating-the-thunderbolt-effect/paged/5/#post-14987
Note how PCIe 3.0 x1 can have performance better than Thunderbolt 3.

Laptop Specs:

• Lenovo Yoga c940 15"
• CPU: i9 9880H
• dGPU: GTX 1650 Q-Max
• RAM: 16 GB
• SSD: 2TB NVME

eGPU Specs:

• Razer Core X Chroma
• RTX 2080

External Monitor Specs:

• 21:9 Ultrawide
• 1080p 2560x1080
• 144 Hz
• LG 34UC79G-B 34"

Hello,

I have had my C940 setup with my RTX 2080 as my eGPU for several months now and I have run into multiple issues.

I have tried doing a bit of troubleshooting on my own over time but I was hoping that you could help me out seeing that you have a very similar setup.

I have 3 overlying issues. I am sure that there is some overlap between them:

Freezes when plugging/unplugging eGPU

Symptoms:

• When I plug in or unplug the Thunderbolt cable from my laptop, frequently the whole system freezes
• This also occurs when powering on my device with the eGPU plugged in
• I do notice that nearly every driver appears to crash when this occurs
  • Sound icon in taskbar shows red X over it
  • Wireless icon in taskbar also shows red X over it
  • If I am on the lock screen when this occurs, the above two occur as well as a message saying something like "We've run into an error" for the fingerprint reader
  • Some other various drivers appear to fail as well

Steps taken:

• Not really sure what I can do to solve this
• Reinstalled graphics driver

Current workaround:

• Hold down power button, forcing restart

Stuck in Sleep Mode

Let me preface this by saying that this may be a completely unrelated error to the eGPU but if you could help me that would still be great

Symptoms:

• Anywhere from 1/10 times to every time my device goes into sleep mode, my C940 gets stuck in sleep mode
• The power button will pulse (indicating that it is in sleep mode) but pressing the power button, keyboard, or fingerprint sensor does nothing
• Hot to the touch where I was unable to leave my hand on any spot of the laptop

Steps Taken:

• I have also tried plugging in and unplugging the eGPU and/or the power adapter which is of no help.
• Fast-Startup is disabled
• I have lost so much data because of this that I have disabled sleep mode altogether at this point
• Created a post on Lenovo Forum: https://forums.lenovo.com/t5/Lenovo-Yoga-Series-Notebooks/Yoga-C940-Stuck-in-Sleep-Mode/m-p/5017724
  • I have not gotten a change to follow the Reddit guide referenced in the forum post
• I have contacted support Lenovo about this (Premium Onsite Accidental Warranty)
  • They almost immediately sent out a repair tech who replaced my entire motherboard/system board
    • This solved absolutely nothing
  • After contacting them again, they were going to send out another repair technician to replace the same part!
  • When I rejected that since they had replaced the motherboard/system board the exact same day, they suggested I factory reset my device (I assume they meant reinstall Windows)
    • This is not an option since I am currently working for my job remotely and cannot afford to have my PC out of commission while reinstalling programs and transferring data 
  • I've given up on Lenovo support to help me with this issue

Current workaround:

• The only way I am able to solve it is if I hold the power button for 10 seconds, force shutting down the PC, and turning it on again. (Same as when PC freezes from plugging/unplugging eGPU)
• If it is super hot, I will leave it off for a while to let it cool down

General Overheating

Symptoms:

• I know my CPU is able to run hotter than others but I feel as though this is still past the limit
• Frequently reaching 100°C
• Can go past 80°C when idle

Steps Taken:

• This was part of the Lenovo service repair referenced above
  • Fans were also replaced but this also did not solve anything

Current workaround:

• If it gets too hot, I turn it off for a while and let it cool down
  • Cannot do this if I'm working

If you can help me out, I would really really appreciate it!