I have seen projects online for converting an ATX PSU into a vairable bench supply. Most bolt an adjustable regulator onto the available switched outputs. But I do not see anyone adjusting the switched output directly from the feeback circuit.

Questions:
1: Can a 12V rail be adjusted for a range (eg 4V-12V) by modifying the switcher feeback sense?

2: If I can, and I do, what kind of trouble might I be getting into? (eg fires, fried equipment))

Backgound:
I do not know a lot about SMPS circiuts. And I know I am not going to get a lab quality...