Daniel Prince wrote:

I have a home built PC with an Epox 8RGA+ motherboard. It has an AMD
Barton 2500+, and a gig of ram. I use the onboard video and sound.
My power supply is an Antec TruePower 420. Where would I look for a
similar working system?

Even the cheapest system sold now is faster.

A $2 digital voltage meter should be more than good enough to tell
whether the PSU or the motherboard is bad, and instructions for
testing can be found in the forums at Overclockers.com and
HardOCP.com, but the locations to measure the voltages on the mobo may
not be obvious. But generally if the mobo is bad, you'll see some
bulging electrolytic capacitors (www.BadCaps.net has lots of info)
around the CPU, next to the north bridge (has a heatsink on it), near
the AGP card slot, or near the DIMM slots, but some caps fail without
showing any physical signs.

Old Antec TruePower PSUs were made by Channel Well Technology (may say
"CWT" on the yellow tape on the transformers) are famous for failing
because of bad Fuhjyyu brand capacitors (Google "Fuhjyyu syndrome"),
but changing capacitors in a power supply can be difficult because
they're stuffed so close together and the better brands of parts tend
to be fatter than the originals. So some of the new caps have to be
installed way above the circuit board (long wires must be insulated
with heatshrink) and physically secured with nylon ties or silicone
sealer. I believe the new Antecs don't use Fuhjyyus because they're
made by different companies, probably Fortron-Source (CapXon caps, not
crowded), Seasonic (OSTs -- well, they're not as horrible as
Fuhjyyus), or Delta (I don't know what brands of capacitors, but
Deltas are among the best power supplies).