radeontop: add page (#3180)

pages/linux/radeontop.md

@@ -0,0 +1,20 @@
+# radeontop
+
+> Show utilisation of AMD GPUs.
+> More information: <https://github.com/clbr/radeontop>.
+
+- Show the utilisation of the default AMD GPU:
+
+`sudo radeontop`
+
+- Enable colourised output:
+
+`sudo radeontop --colour`
+
+- Select a specific GPU (the bus number is the first number in the output of `lspci`):
+
+`sudo radeontop --bus {{bus_number}}`
+
+- Specify the display refresh rate (higher means more GPU overhead):
+
+`sudo radeontop --ticks {{samples_per_second}}`