Category Archives: Nerdy Mind

Raspian remove pi user, add my own user

Adding a new user is easy, but when you login as that user you wont be able to do much. You will probably see no adapter found or no network device detected for your wifi, amongst many other issues with audio devices etc.

Here goes 🙂

from Terminal:

adduser myusername

Enter the password (twice) and just enter all the rest of the info unless you really want to fill it in.

now add myusername to the required groups

usermod -a -G adm,dialout,cdrom,sudo,audio,video,plugdev,games,users,input,netdev,gpio,i2c,spi myusername

phew, nearly there. Do make sure you are swapping myusername for your desired username!

now, still logged in as ‘pi’ user, open the raspian desktop start menu and select ‘Preferences’ -> ‘Raspberry Pi Configuration’ and in the System tab untick the ‘Auto login as user ‘pi’

now use the raspian start menu shutdown option and select ‘logout’. Login as mysername and open a terminal.


make sure your user is a member of all the groups (adm,dialout,cdrom,sudo,audio,video,plugdev,games,users,input,netdev,gpio,i2c,spi), especially sudo

once all good you now reboot and login as myusername then remove the ‘pi’ user using the terminal:

sudo deluser --remove-home pi

good to go. any issue please leave a coment and I will try to help. You can also use the contact form to send me a message.


Raspian, Raspberry Pi Vivaldi browser

so your getting
/usr/bin/vivaldi: error while loading shared libraries: cannot open shared object file: no such file or directory

hmm, try

sudo cp /usr/lib/arm-linux-gnueabihf/ /lib/

While typing that line you might want to press TAB before the .60 in case your version is different?

ok, vivaldi should run now.

Regardless basically you want to copy the chromium provided to /lib/

Let me know if you have any problems and indeed how you fixed it if this did not work for you.


Windows 10 December 2017 update, Caps lock, Num Lock Keyboard LED Lights not working FIX

So you got the Windows 10 update of December 2017 and now your keyboard num lock, caps lock and scroll lock lights (LED) no longer work.

Check windows version as this fix worked for me on this version

open a command prompt by typing ‘cmd’ into the search bar then enter


you should see something like

IF your version is even close this should work fine.

Open Device Manager, and goto ‘Universal Serial Bus controllers’. Start removing ‘USB Root Hub’ devices until your keyboard stops working.

Give it a few seconds, then restart your computer.

All Done. Enjoy


Undervolt explained, Overclocking voltage.

Undervolting, or undervolt means using a lower voltage during over clocking.


All modern IC use a fixed voltage to do their work. If they need to do more work they draw more current at the same volts.

1.2v and no work = 1.2v
1.2v and working hard = 1.2v

Each of the above assumes infinite current.

The over clocking voltage dilemma starts.

A CPU is rated at a meridian voltage based around a minimum and maximum safe voltage.

As reactive loads they do not conform to R=V/I in the sense of a simple resistance. The apparent resistance is reactive to need, not voltage. CPU’s are programmed to know the voltage for a given frequency given infinite current.

More, CPU IC’s are not voltage regulators. Raise the voltage and the same frequency CPU will just dissipate, in heat, the excess. Your CPU will get hot. Try it. Up your voltage but not your clocks.

So, here we are. What is the correct voltage?

Specification of the CPU put it clearly at 4.2Ghz 1.4250v

Manufacture error?

3.9Ghz 1.3850v +_ 10% = 4.2Ghz ~1.4040v