Question about psu testing

[trents]

Got my new Antec earthwatts 650 yesterday and plugged it into one of those psu testers you can get off ebay for $10. Seemed to check out fine except for one irregularity, the -3.3v LED didn't light up, though the +3.3v one did. So I plugged in my old Apevia 500w for comparison and the -3.3v LED lit up. The new Antec 650 seems to work great in my system but I was just wondering why it didn't light up the -3.3v LED on the tester. You would think you wouldn't get any thing from the 3.3v circuit at all if there was no minus side. Maybe the Antec -3.3v side isn't strong enough to power the LED or maybe Antec is just wired differently than the Apevia. Any ideas?

[Old Thrashbarg]

-3.3V? You sure you don't mean -5V? Because there is no -3.3V in the ATX spec. (Although I suppose it could just be mis-labeled on the tester.)

If it's -5V, many newer power supplies omit that, since it hasn't really been used since the days of ISA cards. It's not a problem.

[trents]

Sorry, you are correct. It was the -5v LED that wasn't lighting. My memory deceived me. So, I'm relieved to discover that is no longer used and no show is normal on many of the newer PSUs.

[Oklahoma Wolf]

-5V was dropped from the ATX spec a long time ago.