Sky/Kaby Lake "U" CPU OPI 2GT/s half-bandwidth issue
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Sky/Kaby Lake "U" CPU OPI 2GT/s half-bandwidth issue  

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New Member
Joined: 1 year ago

Sure thing - I've posted the whole guide here

It's quite detailed and tricky at times, but let me know if you have any questions

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.


nando4 liked
Founder Admin
Joined: 5 years ago
Builds: 155

@jkbuha, Thank you! I updated the OP with the link to your tutorial.


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2021 14" Microsoft Surface Laptop Studio [11th,4C,H] + RTX 2080 Ti @ 32Gbps-TB4 (WD_Black D50) + Win11 [build link]  

Active Member
Joined: 11 months ago

I've stumbled upon this thread as I use a Sskylake "U" processor too (i5-7200U) and was wondering if this limitation is the case for me too, since I am getting around 1660 MB/s bandwidth. However, it only shows a PCIE 3.0 x2 connection in HWInfo for me - so I checked out the motherboard schematic to make sure it's physically only connected with two lanes and as you can see m.2 port is indeed only connected via two PCIe-lanes:


HWInfo (m.2 port currently occupied by my NVMe SSD):


 I double checked with the mentioned Dell XPS 9350's motherboard block diagram and there it is (obviously) connected with four lanes:


So from this, I think I can safely conclude that my connection is indeed a 16 Gbps m.2 connection, can anyone confirm this?

This bandwidth did cause me a bit of confusion as there was an "8Gbps-M2" port, and a 32Gbps M2 port, but no "16Gbps-M2" port listed under the "Q: What is the measured bandwidth of the various 'eGPU ports'?" Question, the only 16Gbps connections listed are Thunderbolt ones. It made me look for an error, or if I have the OPI bandwidth problem described in this thread. So maybe we could add this to the list for people who may also have a 16Gbps m.2 connection so they don't get confused by it. On the other hand, it seems like a very rare connection, with only 3 builds currently using that speed on a m.2 connection, and one of them (Zoltan Kiss') actually showing as PCIe 3.0 x4, so it might not make sense to put another row for a very uncommon connection. Or I'm wrong and I could put mine in 4 GT/s mode! Let me know what you think!

2017 15" Lenovo ThinkPad E570 (GTX950M) [7th,2C,U] + RX 580 @ 16Gbps-M.2 (ADT-Link R43SG) + Win10 [build link]  

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