I have chess programs with an Overclocking program trick Outs.
3.2 MHz, 4.6MHz and 4.7MHz.
The screen flickers hertz because of that number at the monitor.
This is the trick so that the CPC can calculate more quickly.
That chess programs can calculate more quickly through it.
I liked to play chess at that time and it went more quickly with it, i have loaded my program Outs previously.
I put in only the monitor V-Hold differently so that the screen doesn't flicker.