Hidrogen generator - electric problem
In the picture you have shown, nothing is connected to one of the terminals on the container.  I assume it is meant to be the yellow wires.

If you are using a PC power supply, then a few possible problems spring to mind:


The power supply may not actually be switching on.  Modern PC power supplies need more than just power going in.  They will sit in standby mode until something tells them to turn on.
The load on the power supply is too low for the voltage regulation to work, and it will not turn on.
The load on the power supply is too great, and it has shut down to protect itself.


If nothing else, you need to check the voltage across your cell to see if there is any voltage.