For testing you can really just hook up a junk hard drive or something like that, should provide enough load for the supply to turn on and you can measure to see if voltages are within spec.CJ -------- Original message --------From: John Heritage via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Date: 12/28/19 10:06 AM (GMT-05:00) To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Cc: John Heritage <john.heritage@gmail.com> Subject: [vcf-midatlantic] Old AT power supplies - how to test? Hey folks,I have a couple of old DOS/Win98 (OS/2) era systems that I came across, andthey both have AT PSUs I want to check out before powering on for the firsttime.I was thinking before powering on:- Open the PSU- Air spray the PSU- Look for obvious signs of failure - capacitor leakage, burnt PCB, burntcomponentsIf all looks OK - do these require a load, or can I at least test basicvoltage with no load?I do have heat resistors (used to balance out ATX PSUs for a 3D Printer)that I believe I can plug in on the 5V or 12V rails and test voltage there..How much testing should I do / what do you recommend?Thanks!John