The MagPi - February 2020

have a Raspberry Pi 4 Stand, you can 3D-print or
laser‑cut your own with the files on our GitHub
page (magpi.cc/github).
Alternatively, place your Raspberry Pi inside
a case designed to manage the CPU temperature
(see our Thermal Cases group test on page 66).

02

Update Raspberry Pi 4
Make sure you are running the latest version
of Raspbian OS. Tweaks to performance are being
made all the time and you will hit faster speeds
with the latest software.
Open a Terminal and enter the following:

sudo apt update

sudo apt dist-upgrade

Now reboot the system:

sudo reboot

This restarts Raspbian.

03

Watch your speed
Before we start overclocking, take a look at
the default CPU speed. Open a Terminal and enter:

cat /sys/devices/system/cpu/cpu0/cpufreq/

scaling_cur_freq

Terminal will most likely return 600000. Divide this
result by 1000 and you’ll get the speed in MHz. This
is the base speed: 600MHz (or 0.6GHz).

This is the speed requested by the kernel. If your

Raspberry Pi is being throttled due to low voltage

or over temperature, the actual CPU speed may be

lower. To get the actual speed, enter:

vcgencmd measure_clock arm

As you use your Raspberry Pi, the requested speed

will boost to its upper level, which is 1500000. You

can keep entering vcgencmd in Terminal to see

where it’s currently at, but it’s better to use the

watch command to monitor the speed.

watch -n 1 vcgencmd measure_clock arm

This keeps vcgencmd running as a process and

updates the result once per second (the -n 1

option is the interval in seconds). Start using your

Raspberry Pi and you’ll soon see the result go

slightly above 1500000 (or 1.5GHz).

Top Tip

Monitoring voltage

It is essential to keep the supply voltage above 4.8 V

for reliable performance. Note that the voltage from

some USB chargers/power supplies can fall as low

as 4.2 V. This is because they are usually designed

to charge a 3.7 V LiPo battery, not to supply 5 V to

a computer.

To monitor Raspberry Pi’s PSU voltage, you will

need to use a multimeter to measure between the

VCC (5 V) and GND pins on the GPIO.

More information is available on the Raspberry Pi

website (magpi.cc/powersupply).

dit the config.txt settings to overclock Raspberry Pi 4E

Insert Raspberry

Pi 4 carefully into

the stand, making

sure the indented

ridge is on the same

side as the four

PoE pins. This holds

Raspberry Pi 4 on its

side, enabling airflow

around components

TUTORIAL

Overclock Raspberry Pi 4 magpi.cc 35