checking power supplys with a basic meter

[primetime]

i know how to check the 5 and 12 volt rails very easily (ripple aside) are there other rails we can check with working meters on today's supply's. I guess the only way would be to insert your test lead into the backside of the 24 pin board connector (if that was even doable)
Or is it kinda stupid and risky to even check those other rails?

 

[Ebernanut]

Sata power connectors have 3.3v pins, they're not as easy to take readings from as a molex connector but it's easier than trying to use the 24 pin connector.

 

[primetime]

Sata power connectors have 3.3v pins, they're not as easy to take readings from as a molex connector but it's easier than trying to use the 24 pin connector.

thank you i was unaware of that.....thats exactly what i wanted to know

 

[FnordMan]

I generally pull all connectors from the motherboard and just check 3.3v from the 24-pin connector. (it'll be orange if I remember right)

One can manually turn a PSU on by shorting the green wire to any black one, i've got a small bit of wire in my multimeter box for just that purpose. (I think it's green, it'll be a unique color)

 

[primetime]

I generally pull all connectors from the motherboard and just check 3.3v from the 24-pin connector. (it'll be orange if I remember right)

One can manually turn a PSU on by shorting the green wire to any black one, i've got a small bit of wire in my multimeter box for just that purpose. (I think it's green, it'll be a unique color)

that seems pretty helpful....got to looking at the sata power connectors and it could be tough checking power on those tiny plugs.(paper clip might help? or very tiny solid wire i guess) but your suggestion sounds a lot easier aside form not being able to check it under load, which i hate to say is preferable even if it makes no difference

 

[dandragonrage]

i know how to check the 5 and 12 volt rails very easily (ripple aside) are there other rails we can check with working meters on today's supply's. I guess the only way would be to insert your test lead into the backside of the 24 pin board connector (if that was even doable)
Or is it kinda stupid and risky to even check those other rails?

Keep in mind if your PSU has multiple +12V rails, they all need to be checked, and you'll need to figure out which connectors are connected to which rail. You definitely won't have all rails on the ATX connector. If your PSU has only one +12V rail then you can check everything at the ATX connector if you so desire. You might see lower voltages checking at a high-power-draw connector like ATX, ATX12V/EPS12V or PCI-E if the system is loaded because a higher load will mean a higher voltage drop through the wiring itself.

Personally I don't think SATA is a good way to go unless you use an adapter. The contacts in there are fairly small and I wouldn't want to stick metal in there for fear of shorting it out. Perhaps if you had a SATA extension cable that you could cut up and use the bare wire ends, but even then it is still easy to accidentally short those out with each other or to the case. I thus do recommend checking things from a Molex connector such as the ATX connector (or the old power connector used for HDDs for +12V and +5V) whenever possible.

 

[primetime]

oh oki got ya...so using one of those sata to molex adapters, possibly with a splitter would be perfect...then you could even check it under load.....very good advice many thanks

 

[larrymoencurly]

Check the +5Vstandby because a few months ago it went to 13V in one of my old Antecs, and the same design for the standby regulator is still found in lots of current PSUs.

I wouldn't poke into a SATA power connector because it's easy to short pins together. I'd rather measure at the orange wires on the 20-24 pin motherboard connector.

 

[primetime]

something like this should check the 3 volt rails under stress pretty well

[/URL][/IMG] and just striping a small piece of orange wire and hook to a Alligator Test Lead to your multi meter......

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course my meter will be used for much more than pc work but so far works great