In the video he has it running just over 1Hz so the flashing of the LEDs can be seen with the naked eye. As he brings it up to about 8KHz everything blurs and goes solid (as you'd expect).

Oh found it on the Reg article - 20khz (0.02Mips)

0.02 MIPS for real? I'd expect about 0.005 MIPS from a design like that.

Many early CPUs took multiple clock cycles per instruction, anywhere between 2 and 10+.

So all instructions are executed in a single clock cycle?

To add, here's a nice table of Meaningless Instructions Per Second for different CPUs:

https://en.wikipedia.org/wiki/Instructions_per_second#Timeli...

It's pretty representative of 8 bit CPU true performance.

I think he mentioned somewhere that he had it running at 50 khz now. http://megaprocessor.com/GBU_speed.html - speed page!