POST & PSU tester recs

[Bob.]

These items can be had for next to nothing, but I'm wondering if there are particular POST test cards and PSU testers that are preferred?

Also appreciated, any other 'must have' devices for computer repair.

Thank for your opinions,
Bob

 

[Blain]

PS testers are must have devices if you repair computers.

 

[aigomorla]

I use the thermaltake one..

Yes its a cheap chinese brand one, but it has reading on each Rail.

however on a multi rail psu, its sort of pointless...
As its limited to 2 rails... and some psu's have 3.


But i use that typically for the 24pin ATX, then i bust out my fluke multimeter for the Molex/PCI-E rails and do that manually.

 

[Bob.]

Thanks for the recommendations, Blain & aigomorla.

aigomorla: I actually already ordered the one you recommend. Looks like a better one than most. I guess I'll have to get up to speed on manually checking with a VOM as well.

Thanks again.

 

[Deders]

Considering that they can't test PSU's under load, when voltages can change considerably, how necessary do people think they really are.

I understand they can tell you if some PSU's are bad, just not all. I'm considering investing in one but I'm dubious as to how useful it will actually be.

 

[Bob.]

Considering that they can't test PSU's under load, when voltages can change considerably, how necessary do people think they really are.

I understand they can tell you if some PSU's are bad, just not all. I'm considering investing in one but I'm dubious as to how useful it will actually be.

Maybe the fastest way is to just have a spare PSU on hand to swap out. That said, I'll still be doing my homework. Any good links outlining the proper way to test with a meter appreciated.

 

[aigomorla]

Considering that they can't test PSU's under load, when voltages can change considerably, how necessary do people think they really are.

I understand they can tell you if some PSU's are bad, just not all. I'm considering investing in one but I'm dubious as to how useful it will actually be.

your absolutely correct on that statement.
It cant test the PSU under load, however it will tell you flat out if the PSU is bad b4 u install it and test the rails manually.

That is why i have a multimeter to test while PSU is under load.

Maybe the fastest way is to just have a spare PSU on hand to swap out. That said, I'll still be doing my homework. Any good links outlining the proper way to test with a meter appreciated.

not really, because if the PSU is bad to begin with, it makes your debugging tedious.

Lots of reasons why a system wont post..
Ie. bad cpu, bad ram, bad video card, bad board, short somewhere on the board.

At least with a PSU tester, you can rule out post issues on the PSU b4 you begin.

Because a system at Post will not put a lot of load on the system.
This way u can rule out the others during post and then during load testing, you can fine tune your debug to rule out other parts which you are trying to debug.

 

[Bob.]

your absolutely correct on that statement.
It cant test the PSU under load, however it will tell you flat out if the PSU is bad b4 u install it and test the rails manually.

That is why i have a multimeter to test while PSU is under load.



not really, because if the PSU is bad to begin with, it makes your debugging tedious.

Lots of reasons why a system wont post..
Ie. bad cpu, bad ram, bad video card, bad board, short somewhere on the board.

At least with a PSU tester, you can rule out post issues on the PSU b4 you begin.

Because a system at Post will not put a lot of load on the system.
This way u can rule out the others during post and then during load testing, you can fine tune your debug to rule out other parts which you are trying to debug.

Thanks...good info and makes sense. Multi-layered troubleshooting of sorts. I've been checking out PSU testing on line. Testing with a VOM seems pretty straight-forward, but so far, the only tests "under load" I've come across is having a case fan hooked up, which hardly seems adequate.

I'm guessing here, but is there a way to test it under load by leaving it hooked up to the system and testing connectors that are on the same rail as HDs, etc.? Just what is the accepted way of testing under load?

 

[mindless1]

^ Yes absolutely. If the PSU stays on then you can insert multimeter probes into the back of connectors, but most probes may need a needle attachment to get down into the plug or to pierce insulation if access from the back into the plug isn't reasonable. At that point, you would replicate the usage scenario where the system was turning off and take the readings... not necessarily trying for the highest load the system can manage but rather the least load that is allowing the problem to be seen, especially for the following reason.

If the PSU is running well enough to stay turned on but failing (out of spec) under load, then the odds are you have bad capacitors and shouldn't really be subjecting the system to that, as it is the most dangerous time for the system if the PSU stays running but isn't working properly.

For this reason I don't recommend load testing if you feel the PSU performance is off, until after either:

A) Swapping in a different PSU if the one in question is under warranty still.

B) If warranty is expired, open it and check for vented capacitors. If caps are vented there's no point in doing the load tests, it needs replaced or repaired.

C) Spend the money (or DIY build...) on an independent load testing device. It need not be very fancy, just some connectors, switches, power resistors, heatsinks and fans would suffice. This is more in the realm of professional reviewers or electronics repair personnel, not computer shop level, modular component replacement type repair work.

As far as other load testing goes if the PSU won't stay turned on, you can consult the PSU spec sheet to see what the minimum load specification is. Often it may be around an amp or two on the 5V and 12V rails and for some fancier server PSU, also on the 3.3V rail. If you have a bunch of old HDDs lying around they can be used to cause that load.

 

[Bob.]

Thanks, Mindless1. That's very helpful information.

 

[PhIlLy ChEeSe]

Considering that they can't test PSU's under load, when voltages can change considerably, how necessary do people think they really are.

I understand they can tell you if some PSU's are bad, just not all. I'm considering investing in one but I'm dubious as to how useful it will actually be.

buy a multi meter instead, still will have to place the PSU under load as you said. But you'll get true readings.........

 

[Bob.]

buy a multi meter instead, still will have to place the PSU under load as you said. But you'll get true readings.........

Thanks, Philly. I happen to have about a dozen of those. My filedpiece clamp meter even has a set of molex leads (a bit awkward due to it's amp clamp, though).

 

[Bob.]

Just posting back here with additional info. It turns out that the PSU tester aigomorla linked to (and the one that I had already coincidentally ordered) can test under a load. It's really a pretty complete tester. Not to say that a meter wouldn't be a more reliable method, but with this tester, you plug in your 24 pin, cpu 8 pin (if applicable), sata cable, pci cable. I then plug additional sata cables to an HD and a molex cable to a fan. Then push the button for 5 secs to enter mode B (auto scan). It'll run through the connectors. If there are voltages out of spec, the background turns red, the tester buzes and stops on that test mode (i.e., sata plug).

Handy.

 

[Deders]

Just posting back here with additional info. It turns out that the PSU tester aigomorla linked to (and the one that I had already coincidentally ordered) can test under a load. It's really a pretty complete tester. Not to say that a meter wouldn't be a more reliable method, but with this tester, you plug in your 24 pin, cpu 8 pin (if applicable), sata cable, pci cable. I then plug additional sata cables to an HD and a molex cable to a fan. Then push the button for 5 secs to enter mode B (auto scan). It'll run through the connectors. If there are voltages out of spec, the background turns red, the tester buzes and stops on that test mode (i.e., sata plug).

Handy.

I wish it would tell me which voltage was out.

 

[Bob.]

How would that help (not skeptical, but curious)?