What faults did the tester indicate?

Without any further knowledge (pictures etc), the 47 ohm resistor could be a dummy load, so it is meant to just sit there and consume power in order to keep the output voltages stable. Sometimes a minimum current draw is needed to keep feedback loop happy and the internal resistor guarantees it.

How did you do the continuity test? Was there a resistance reading near zero? Some multimeters just beep if the resistance is below 100 ohms or something similar, so for a random multimeter whose workings are unknown, I would not trust the continuity test mode but just resistance reading.

My suggestion is to just connect the PSU to mains and see if 5V standby is there (purple wire). Then to start the PSU you connect the green wire (PSU_ON) to ground (black), and the rest of the voltages should appear. And again, sometimes the PSU needs some minimum load (hard drive or two) to get correct output voltages.

Thanks for the tips!

My tester shows +5v=HH, -12v=LL, and +12v1=LL (+12v2 is also LL, but it is an old unit with no 4pin 12v connector). PG is fine.

I tested the purple 5vsb and it is 4.95v, so that seems fine.

My "method" for testing the continuity was nothing special (or even accurate apparently). I'm using a Fluke Model 75 multimeter. With the unit unplugged I merely tested the continuity at the ATX connector. All of the black wires, the red wires and the orange wires would cause it to beep when any of them were connected. I'm an electrical newbie so I see now that they do have a resistance of between 14 ohms and 40 ohms roughly... I'll try to remember to pay more attention to the readout when testing for continuity problems in the future.

I just tested it manually using the paper clip and testing the voltages with my DMM (all testing done at the ATX connector). +5v reads 5.55, +3v reads 3.33, +12v reads 10.85 and -12v reads -10.48.

It seems the tester is right in that the +5v is quite high and the +12v is too low... I guess I could use an old bad drive to see if a small load brings these numbers up to spec.

Hah!

Thank you Jepael...

Adding a hard drive got the tester to stop complaining, and adding a second brought the voltages even closer to spec. With two drives connected, when I measure with my DMM I get +12v=11.76, +5v=5.24, 3.3v=3.35, -12v=-11.76.

Much better! A couple of my old drives are apparently more dead than I thought though. The PSU would squeal significantly with them connected and one of them actually made it shut off after a few seconds. My other ones don't do this at all.

I intend for this PSU to be used for some kind of beefy older system since it can supply 30a on the +5v and 12a on the +12v rail.