To find the temperature of the GPU and ARM CPU on a Raspberry Pi running Linux, you can use the vcgencmd command. This command is used to get and set various parameters of the VideoCore GPU and ARM CPU on the Raspberry Pi.
To find the temperature of the GPU, you can use the measure_temp subcommand. For example:
vcgencmd measure_temp
This will output the temperature of the GPU in degrees Celsius.
To find the temperature of the ARM CPU, you can use the measure_clock subcommand with the arm parameter. For example:
vcgencmd measure_clock arm
This will output the clock speed of the ARM CPU in Hz, which you can use to calculate the temperature using the following formula:
temperature = (clock speed - 600 MHz) / 3.5
Keep in mind that the temperature of the GPU and ARM CPU may vary depending on the workload and ambient temperature.