This is a PSU to replace one that is currently failing...
The ratings on the Macron are almost twice as good as the current PSU.
I'm not wanting to spend more than $50 CDN on a PSU, so these are the two
that I have available.
I don't deal with these two generic "labels", though it's quite
possible I've seen the same power supplies with a different generic
label on them. The funny thing about them is that when systems
started needing more power, say around the time of the ~1GHz Athlon
systems' debut, suddenly many generic power supplies starting wearing
labels claiming greater capacity with NO HIGHER true output. It's
possible these power supplies have higher true capacity than your
current power supply, but on the other hand almost all the 400W
generics I"ve seen have lesser true capacity than a name-brand 250W
model. Name-brand is your assurance of a minimal level of quality and
capacity, far moreso than the numbers on the label, which can only be
relied upon from the better manufacturers, otherwise only between
different models and series from the same manufacturer.
For $50 CDN, which I roughly translate into $35 USD, you're cutting
the power supply budget pretty tightly. There's a certain minimum
price for a power supply that doesn't skip any important features, $35
is a challenging price-point to shop for. Not knowing the going
rates where you're located it's hard to suggest a make/model with such
a small price-window, but I'd look for a 300W Sparkle or Fortron
(essentially the same power supply, different label). Those models
typically have one of the best quality per dollar ratios without any
unnecessary frills adding to the cost. You don't mention the system
so I can only assume it's high enough capacity, since you did mention
the previous power supply being rated only half as well as those
generics.
Dave