The Mastech was blazing hot & funding multiple PG&E pensions, so decided to hack the 21 year old AT power supply to generate enough voltage for the Lighting Evers.  It now only generated 11V & its fan was broken.  It sagged to 10V with the LEDs on.  All voltage regulators have a feedback pin. 

http://danyk.cz/at_atx_en.html

http://electronics.pl7.de/power-supplies/power-supply-from-2-4-to-23-volts-adjustable-from-an-old-at-or-atx-psu/

The internet said pin 1 of the A1K494 was the feedback & these boxes could reach 16V before capacitors started blowing up.  It was connected to a nasty resistor network.  A 35k was the most likely replacement.  Managed to raise the no load voltage to 13.75 but no higher for any resistance above 118k.  The 35k seemed to be parallel with a 3k, but whatever.  Replaced the 35k with the 118k.  With the LEDs on, it sagged to 12V.  

Maybe higher voltage could be achieved by returning the 35k & disconnecting pin 1 from the circuit completely.  Then provide a scratch built divider for pin 1.  It all seemed too much trouble, compared to replacing a single resistor.  There might be other issues with over voltage protection & short circuit protection.  Any sane lion would just buy a proper supply & wait 3 weeks.

Things were a bit dimmer than the Mastech, but much more efficient.  The old fan was relubricated & it worked just like 1997 again.  Hard to believe this 235 watter with no insulation on the manes pins & all its sagging was the lion kingdom's very 1st power supply.  It powered the very 1st experiences capturing video, something you'd think would require much more.