Chosen Solution
I just pulled this from my Dell Precision 7500 and it does not look like the original power supply. Any suggestions on how good it is and how to test if it works?
That likely is original to the T7500. Those units were from a time Dell had issues with bad capacitors from time to time, but the issue shifted from bad motherboards to the power supply. Those are old enough to use a standard 24-pin ATX supply, but it may leave a gap in the power supply area (it’s not much anyway, tbh). You can get a new one and do it that way, but the other option is to bridge green and a black ground wire (green=PWR_GOOD) and measure the other rails, but bear in mind this is an UNLOADED TEST; it may pass unloaded but once you start putting a load on it is when they fail. However, if the capacitors are bad, it’ll be obvious with a 1-2V+ loss depending on how many are bad. You may be able to find a power supply tester (which will put a load on it, albeit small) but these supplies can “pass” when they have issues especially with how power-hungry old LGA771 Xeons can be compared to modern ones, or even a LGA775 65nm Core 2 Quad – the 45nm ones weren’t as bad, but those old ones like the Q6600 had ugly power consumption figures due to the Conroe core. Even the modern ones aren’t power sippers, but these old 771 Xeons were rough at times. An intermittent power supply WILL cause issues if it’s bad enough.
