You have 'hit the nail on the head' when trying a replacement, I can't
comment on the Hipro as I never come across one.
A replacement works so it proves the point that there is a fault with
the Hipro psu, the cause could be just about anything from a loss of a
rail voltage, ripple on a supply or supplies due to bad electrolytic
capacitors... or even poor regulation due to the feedback loop between
secondary and primary usually done via a opto coupler.
This link might throw some light 'About PSUs'
(
http://www.answers.com/topic/power-supply-rail) and 'About Power
Supplies' (
http://murfsgarage.cybertechhelp.com/Power.htm)... I'll
throw another useful gem in about calculating the 'Wattage required.
' (
http://www.journeysystems.com/?powercalc)
Under no circumstance power it would with no load... at least on the
5V 20 Amp or so rail or you 'may' end up seeing fireworks.
Davy