Computer power supply tester; buy which one?

They're all pretty worthless, just buy a multimeter. You can poke the probes in the back of the ATX connector while the computer is running.

Both are practically worthless; about as effective as a "check engine" light on your car's dashboard. They won't test the power supply under load conditions.

Really? A power supply tester is handy if you have to go through a lot of power supplies. I have two other models that see a lot of use. In fact, I used one a few days ago to show someone that their supply was bad. Its true that a cheap tester won't find EVERY problem, that do kick out a lot of the bad supplies faster than a voltmeter and jumper. it also eliminates the motherboard's power control circuit and front panel switch. i have seen plenty of bad switches, and a number of bad motherboards that wouldn't turn the PS on.

You disconnect the 20 or 24 pin cable from the PS at the motherboard and connect it to the tester. It puts a load on the +5V supply, and allows you to meter the voltages. I have never seen one made to be used along with the motherboard.

If you have 100 psus and need to do a quick check on them the tester could have some value, but for what the OP requested, the tester will be next to worthless. If you want to evaluate the condition of just one or two psus, you have to do much more extensive testing.

James, I built test fixtures at the Microdyne factory to test power supplies for their $20,000 to $80,000 telemetry receivers. We did a lot of tests to EVERY one of the $700+ power supplies before they ever got close to a radio. You have to know your test equipment, and when to use what. Denying yourself some simple tools for quick tests is a stupid as trying to work with no test equipment.

Which is exactly why one buys the multimeter and does not use a 'magic box' power supply tester. The former provided a definitive answer and with numbers that can obtain further useful information. The latter (power supply tester) hardly applies a load, does not really say why it is 'go or nogo', and never really provides a definitive answer. Get the meter because one needs simple tools for quick and reliable tests. A tool that is also useful for solving other electrical problems - not just the power supply.

Power supply tester will not even provide a definitive answer AND makes useful assistance from others almost impossible (no numbers).

Yawn. Go troll somewhere else.

Michael must denigrate when he cannot technically justify what he posts. Michael was a technician who wired boxes without knowing what those boxes did. An informed lurker uses a meter as recommended by many others; ignores a technician who must attack the messenger. Why? He cannot technically defend his recommendation.

hmmmmmmm a MULTIMETER is gonna apply even LESS of a load than a power supply tester. basically computer power supplys work or they dont , all he . me want to do is see if they work or not.

why wont the power supply tester work ?

multimeters put less load on than the computer power supply testers.

a MULTIMETER puts a LOT LESS LLOAD on than a power supply tester. a multimeter will show the same results as the tester , wether there is the corrct voltage or not....simple.

"mark krawczuk" wrote in message news:460ae159$0$24862$ snipped-for-privacy@pit-reader.telstra.net...

No.. it's not that simple. A PS tester puts a minimum load on the main regulated output of the PSU; just enough to allow the PSU to come up. All the other outputs are totally unloaded. The tester only provides an "idiot light" indication of the condition of the PSU, whereas a digital multimeter, even a cheap one, will provide a qualitative indication of each of the PSU outputs... and under actual loaded conditions (if the PSU is left connected in the PC). With those measurements, you can make a much better determination of the condition of the PSU. Who knows the voltage limits of the LED indicators on the tester? Nobody specs that for their testers, at least for none of the testers that I have seen on the net. With a multimeter, you will know, with known accuracy (within the spec'ed accuracy of the DMM), what the actual output voltages are. The tester won't give you that info. True, the DMM still doesn't give you the total picture, such as ripple and noise on the outputs, but knowing the actual voltages on the outputs is an order of magnitude better than what the "idiot lights" tell you. Yes, it takes a bit more time to check each output individually with a DMM, but it's a much better test. On second thought, it might even take less time to check with a DMM, because you don't have to disconnect the PSU from the motherboard, then hook up the tester, then turn on the PSU. With a DMM, you only have to gain access to the PSU connector and touch the probes appropriately.

As far as testing a pile of PSUs, I guess you can use a tester to cull out the obviously dead ones rather quickly, but beyond that, I question its value.

And?

-- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85.

Michael A. Terrell Central Florida

Please read the procedure before posting. Standard procedure: never disconnect and never remove anything until AFTER data is collected. Disconnecting a power supply or using the power supply tester; both are testing with virtually zero load - not informative and not useful. And both do disconnecting. Meter in but two minutes does best test because nothing is changed or removed. Best load is motherboard and active peripherals. Best data is numbers; not a GO/ NOGO light. No numbers and no load from a power supply tester reports little that is useful and provides no useful (and further) information from newsgroups.

See DaveM post for further information. Get the meter to save time, accurately repair the first time, and become informed as to why things fail. Shotgunning or that power supply tester reports so little and teaches nothing.

Yes, that's what the rest of the computer is for. As I said, poke the probes into the *back* of the connector pins while the PSU is powering the motherboard.

No they don't "just work or they don't". All kinds of things can go wrong with power supplies. Output voltage can be too low or too high or sag under load, there can be excess ripple, glitches, plenty of faults only show up when heavily loaded. I just replaced an Antec power supply recently that powered up fine and all voltages checked out ok, but the outputs would gradually sag under load until the computer would just randomly shut off. A PSU tester would have passed that one with flying colors but it failed in service and using a multimeter while it was operating the computer in question was the only way to diagnose it.

Yawn. Give it up Tommy boy. You have to spread lies about anyone you disagree with. Why don't you just go back to news:alt.usenet.kooks and leave these good people alone? You never contribute anything useful. You only copy & paste your views on surge protection, while citing quotes from agencies that are long gone.

No matter what you say about me, makes no matter because you are simply an anal retentive usenet kook and and love to start flame wars. Tell me, do you have Google groups email you every time your name, or surge protection is mentioned? The engineers on news:sci.electronics.design have repeatedly driven your spew into the ground, and all you can do to counter it is to copy & paste the same old crap.