USB 3.0 on Linux ( AMD processors )

You'll find at times that your USB 3 device is running on USB 2 speeds. This  can be addressed by passing a  kernel parameter in grub. "amd_iommu=on" 

The input–output memory management unit (IOMMU) is a memory management unit (MMU) that connects a direct-memory-access–capable (DMA-capable) I/O bus to the main memory.

To make the changes permanent, add the parameter to /etc/default/grub 

GRUB_CMDLINE_LINUX_DEFAULT="amd_iommu=on"

and run "sudo update-grub"


Remember that  the effective transfer rate will be dependent on internal disks and other possible bottlenecks . 

TP-Link TL-WN725N wireless USB adapter on Linux

The default driver which is auto loaded by the kernel does not seem to work as expected . The workaround is simple. Go to the TP link site here : 

https://www.tp-link.com/us/download/TL-N725N.html#Driver

download the driver , unzip the file and ,

$ apt-get install gcc

$ make clean
$ make


then


$sudo cp 88x2bu.ko /lib/modules/[kernel version]/kernel/drivers/net/wireless/ #[kernel
version] is the directory name of the system kernel version

$ sudo depmod  –a
$ sudo modprobe 88x2bu.ko

in my case it was 8188eu.ko

lsmod to check

Blacklist the existing module by adding  the line

blacklist   r8188eu

to  /etc/modprobe.d/blacklist.conf 

unplug the dongle and plug it back again .

Seems to work perfectly now! :)