According to USB 3.0 specification it can handle up to 5Gbps (640 MBps) which is over ten times as fast as the USB 2.0 maximum. However, there are different factors which interfere and prevent the Intel® NUC d54250wyk (and any other electronic devices which use the USB 3.0 specification) from reaching the highest data transfer rates proposed.
In this particular case I suggest confirming the Samsung EVO* 850 mSata data transfer speeds and also the Western digital* drive transfer speeds supported according to each manufacturer's specification.
*Other names and brands may be claimed as the property of others.
Thank you. I've already made sure the drivers are the most current and I've tested the transfer ratte on the Samsung mSata with the same benchmark and it gets well over 4000MB/s. I wonder why the USB is sooo slow.
I resolved the issue. I first removed the Enhanced USB host controller in the device manager and rebooted. Upon reboot it was re-installed however the driver that was automatically re-installed was from 2105 and the old on was from 2006. Also there was a setting for USB 3.0 in the bios set to disabled. I enabled that too.