I have a relatively new USB 3 hard disk: Seagate 2TB Backup Plus Slim Portable External USB 3.0 Hard Drive (Silver) Also, I have an USB 3 SD card reader. Both of these are known to work faster than they do now. They perform at 40-45 MB/s.
I use USB Device Tree Viewer V3.1.2 and it tells me these, for both devices:
Device Bus Speed : 0x02 (High-Speed) Flags : 0x02 DevIsOpAtSsOrHigher : 0 (Is not operating at SuperSpeed or higher) DevIsSsCapOrHigher : 1 (Is SuperSpeed capable or higher) DevIsOpAtSsPlusOrHigher : 0 (Is not operating at SuperSpeedPlus or higher) DevIsSsPlusCapOrHigher : 0 (Is not SuperSpeedPlus capable or higher)
My motherboard is ASUS MAXIMUS V GENE and it has two USB 3 options. There is ASMedia USB3.0 eXtensible Host Controller and there is also Intel(R) USB 3.0 eXtensible Host Controller. I never got any device to work at USB 3 speed on the Intel. They don't supply drivers for Windows 10 64bit as it is already included in the OS. Then I started plugging devices to the ASMedia ports, and they worked in the past. But I checked again and now all devices are using USB 2 speeds on these ports too. I think what messed it up was a recent Windows Update. I used IObit Driver Booser which complained that the driver was too old for this controller.
Driver: \SystemRoot\System32\drivers\asmtxhci.sys (Version: 184.108.40.206 Date: 2017-11-28)
No joy, even tried manually installing specific drivers. ASUS has this as "latest driver" on their site: Asmedia_USB3_V220.127.116.11 I downloaded it and installed it. Install is successful:
Driver: \SystemRoot\System32\drivers\asmtxhci.sys (Version: 18.104.22.168 Date: 2016-04-14)
But no USB 3 speeds whatsoever. I ran out of options to try.