Page 1 of 1
How to tell?
Posted: Wed Aug 15, 2007 1:37 pm
by Merlin
OK so now I am reaching. I WAS going to abuse my credit and order a new PSU even thuough I can't really afford it but alas I can't do that in good conscience. Ok so EVEN a one armed monkey could possibly hit a three ponit shot so it is possible that Aspire did make a few PSUs that are OK right?? Assume I want to find out IF my PSU really needs to be replaced or IF I got lucky and have a good one. Is there a way to test it to find out IF it is stable or not? then is it a test I can do at home or do I have to have some "rig" to do it?
Re: How to tell?
Posted: Wed Aug 15, 2007 1:52 pm
by Illuminati
If you have a volt-meter or multi-meter, you can test the stability of the voltage rails... If this is a possibility, let us know and we can tell you what color wires you need to touch for what voltage rails.
Re: How to tell?
Posted: Wed Aug 15, 2007 2:17 pm
by Merlin
I do have a small Volt meter...nothing that can read through the insulation. What about mother board monitor 5 does that give accurate info? also IF MBM5 is okay what program should I use to stress the system?
Re: How to tell?
Posted: Wed Aug 15, 2007 3:01 pm
by dicecca112
you touch it to the molex connectors, and no mBM5 is not accurate.
Re: How to tell?
Posted: Wed Aug 15, 2007 3:03 pm
by Merlin
OK yes I do have a volt meter. Would you mind give me instructions on how to test including what to set the volt meter to? Is there not a way to test it under load?
Re: How to tell?
Posted: Thu Aug 16, 2007 7:04 am
by Illuminati
Wires from you PSU:
Orange = 3.3 volts
Red = 5.0 volt
Yellow = 12.0 volts
Use the red wire on the volt meter and touch the metal of any connector coming from the PSU. Touch the black wire from the volt meter to a black wire on the same connector.
For the 5 & 12 volt rails, you would usually take the readings from a 4 pin molex connector. But for the 3.3 volt rail, you have to take that reading from 24 pin ATX power connector. You can usually shove the volt meter connector in the back of the connector right next to the wire and get contact with the bare wire.
if you PSU has multiple 12 volt rails, you will need to determine what connectors you would need to test to check the different 12 volt rails.
and lastly, to test your PSU under load, you just have to put stress to it while the volt meter is connected. usually, having as many fans connected as possible, playing a DVD or CD in the optical drive, running folding@home, and running 3dmark all at the same time will put sufficient load on your PSU to determine how stable it is.
post back with any other questions and/or results! Be Careful!!!
Re: How to tell?
Posted: Fri Aug 17, 2007 11:10 am
by Merlin
Should I test it first by itself, turned on but not connected to get a baseline reading? How risky is this really? I have been running this PSU since I upgraded over 6 months ago. IF I dont make any system adjustments would it be more risky to test it or leave it alone?
Re: How to tell?
Posted: Fri Aug 17, 2007 12:15 pm
by kenc51
Merlin wrote:Should I test it first by itself, turned on but not connected to get a baseline reading? How risky is this really? I have been running this PSU since I upgraded over 6 months ago. IF I dont make any system adjustments would it be more risky to test it or leave it alone?
It's only risky of you cross wires. or somehow touch the 12v rail. Before you power on the PC, you should attach your probes and power on the DMM....this way there's less chance of slipping and causing a problem.
Here's a link to a guide
http://forums.extremeoverclocking.com/s ... p?t=137886
Re: How to tell?
Posted: Fri Aug 17, 2007 11:45 pm
by Merlin
so how the hell do I keep the volt meter attached and still run my PC?? Just jamb the probe into the connector from the back and pray That I dont do something wrong. This cant be the best way if it is then we have to build a better tester. I have seen testers at Fry's that can test a PSU unplugged but we could make one that was like an adaptor that had a volt meter attached so you plug your PSU into the meter then the meter into the Components and run your PC. REad results and done. IF its this hard to determine what is a good PSU and a bad one how the heck are we (the normal non-tweaker consumer) supposed to know??
These are the things that help to make Dell and others so rich. If no one can tell what they should buy then everyone will just let Dell deal with it and pay out the nose for the "service contract"
P.S. Sorry but this whole PSU thing really chaps my butt, I dont want to take a chance a blow my rig but I dont ubdestand how NewEgg can sell an $80 PSU that everyone now says is a POS but Corsair who didnt even make PSUs 2 years ago now makes one of the best ??? It makes me mad that a normal guy CANNOT tel what is good and what is not.
Re: How to tell?
Posted: Sun Aug 19, 2007 7:17 am
by kenc51
Merlin wrote:so how the hell do I keep the volt meter attached and still run my PC?? Just jamb the probe into the connector from the back and pray That I dont do something wrong. This cant be the best way if it is then we have to build a better tester. I have seen testers at Fry's that can test a PSU unplugged but we could make one that was like an adaptor that had a volt meter attached so you plug your PSU into the meter then the meter into the Components and run your PC. REad results and done. IF its this hard to determine what is a good PSU and a bad one how the heck are we (the normal non-tweaker consumer) supposed to know??
These are the things that help to make Dell and others so rich. If no one can tell what they should buy then everyone will just let Dell deal with it and pay out the nose for the "service contract"
P.S. Sorry but this whole PSU thing really chaps my butt, I dont want to take a chance a blow my rig but I dont ubdestand how NewEgg can sell an $80 PSU that everyone now says is a POS but Corsair who didnt even make PSUs 2 years ago now makes one of the best ??? It makes me mad that a normal guy CANNOT tel what is good and what is not.
The PSU tester you see in Fry's won't test the PSU under load, You'll need alot more expensive hardware to do that.
You should be able to grab an un-used molex cable from the PSU, if you have to sit the case on it's side so the cable can reach, so be it. What you want is for the multimeter to be sitting on the desk / floor and for the cable to reach it. You should be able to insert the probes on the meter into the molex connector. As long as you don't move the meter/probes/cable, it will stay in there. If you knock it out, chances are nothing will happen. I've probed various parts/components on my board while it was running, and even when I slipped, nothing happened. Just make sure the black (ground) probe doesn't touch the same thing as the red one, as you can say good bye to what ever part it is.
I normally attach the black one to a seperate molex cable and leave it there. Then use the red probe to touch the Yellow (12v) then the red (5v) and also the orange (3.3v) in turn.
You can attach the black probe to any black cable and leave it there!
If your testing the 3.3v it's best to push the red probe into the ATX connector, probe the orange cable. Do lthis when it's powered off, as you could slip.
If your carefull, the risk is minimal. I've done this tons of times with the rig running.
When your taking readings, do it when the PC is idle at the Desktop, then load up diskkeeper or windows defrag and defrang your HDD's, also open Orthos etc. to stress the CPU and also loop the firefly test in 3dMark '06. This will simulate a worst case sinario for power drain.
An $80 PSU could be ok for rigs today, but might not. Todays PC's pull alot more AMPS on the 12v line than a few years ago. This is why PSU's are now so important.
Corsair sell some of the best PSU's, but they don't make them. Seasonic makes the PSU's for Corsair. Corsair were just smart and knew their market before entering into this market.
The Corsair 620W is basically the same as the Seasonic S12, just Corsair's primary capacitor is rated for 105C instead of 85C, most likely because of their warranty. 85C vs 105C capacitors in this design of a PSU is a mute point IMO as the PSU's are inherently cool running anyway ;)
The basic design for this PSU is very effecient, this is what makes it so good. Dicecca might know more about this

Re: How to tell?
Posted: Sun Aug 19, 2007 1:28 pm
by Merlin
I appreciate the help and I am sorry for being a bit of a grouch (cleaned it up...wanted to say somethin else) about this. I am just mad about the whole thing cuz I can't afford to buy a new PSU and I can't upgrade my PC until I do which translates into a whole lot of I CAN'Ts which makes me grumpy.