I have (2) Thinkpad 8 devices and neither are achieving USB 3.0 speeds when connected to a USB 3.0 device.
under device info (in the Charms menu), it says
"device can perform faster when connected to USB 3.0".
That means for whatever reason, the system is NOT seeing a USB 3.0 connected and is slowing down to USB 2.0.
I looked at the USB tree viewer and it shows my device's bus speed is USB 2.0 (the device itself is certified USB 3.0 and I have checked the device in another laptop with USB 3.0 and it works like it should).
I am unable to get speeds about 30 - 35 mb/s which is the upper limit of the USB 2.0 spec.
What is the problem?
The TP8 uses a Micro USB 3.0 (a) OTG cable. Many cables on the market that are marketed as USB 3.0 are Micro USB 3.0 (b) OTG cable. These are the ones that are widely available for the most part on Amazon, Ebay, etc. which will provide connectivity, but may not deliver the full USB 3.0 speeds.
A micro 'A' cable identifies one end of the cable as the host end. There is a host ID pin within the Micro A connector that performs this function on a properly designed OTG cable. Since theThinkPad Table 8 can operate as a host device, per the USB spec it needs to use the Micro A/B connector type.
One cable that is proven to work and deliver full USB 3.0 speeds is the Lenovo cable P/N 4X90F84314
Using this cable, or other correctly wired host type A micro USB 3.0 cables should be recognized in Windows as providing USB 3.0 connectivity and performance.
We have confirmed that cables which do comply to the USB 3.0 spec work at 3.0 speeds with Tablet 8.
There is nothing wrong with the Tablet 8 port, and it properly follows the spec.
Another option is the recently released Y cable that provides USB connectivity and charging capability. Part number 4X90G54343
Some members of the community have reported that the BIOS of the tablet 8 should be updated to ensure proper operation with the Y cable. Please visit the support site and update to latest version.