- Did you ever need to test your power supply?
The best way to do it
is to use a power supply unit tester, or PSU tester.
And these are those 24-pin connectors
that'll connect right to the main power.
We're gonna show exactly how to use this,
and how to read the results from that tool.
Let's get started with that now.
Here are some power supply testers,
and they go from oldest to newest.
And I also have a USB power tester,
and we'll show each of these.
Let's describe each one real quick.
First, we have this old one here,
which is an AT 20-pin power supply tester,
which you can also use for the 20-pin connector,
if it's separate from your 24-pin connector,
if the 4-pin is separated from it.
And you'll see here that we have the +12 volt,
the -12, the -5 to +5, +3.3.
The main voltages you wanna check.
So this is an old school power supply tester.
But if you come across some older power supplies,
this is a good guy to use.
Then we move into the Thermaltake power supply testers.
And that's just one manufacturer.
That's generally who I use.
And here's one that has the 24-pin connector.
So that works with ATX power supplies.
And then on the other side, you have Molex,
and you have a 4-pin for the CPU,
and also an old school 4-pin mini connector,
or Berg connector,
which was used by floppy drives.
So if you have those older devices with Molex
or that type of thing, you can test it with this guy.
And these lights light up,
telling you whether the voltages are good or not.
Same type of thing, +5, -5, +12, -12, +3.3.
And also, this one has a +5 standby,
which is what ATX power supplies use.
If you have the computer plugged in and the computer is off,
it's still feeding 5 volts for standby.
So you can turn the computer on and it'll activate.
Or it can be woken up on the land, or that kind of thing.
So that's the +5 standby voltage.
You may or may not see that lit
on some power supplies, it depends.
But usually, you will for ATX.
And then the newest one here.
This is the Thermaltake Dr. Power II.
Got your 24-pin connector.
Works with the latest ATX as of the recording of this video.
And then here, we have the old school 4-pin Molex,
which you might still have.
But we also have those 8-pin power rails that you see
most commonly now on today's ATX power supplies.
And we showed that when we built the AV Editor computer.
And you have your red and your black.
You might be using these for video and hard drive and so on.
Now these are passive devices.
They require no batteries.
They use the power flowing through the connection.
So the computer has to be on for them to actually work.
They operate on the power from the computer
once you plug it in, which is,
that's nice to passive, no batteries required.
And finally, we have a USB tester.
And this will test the voltage
that's coming from your USB port.
And it'll display how much, what the voltage is
so you can make sure that it's working properly.
And normally you want it to be right around 5 volts.
And then you have outputs here.
So you can plug in devices
and see what they are pulling, as far as amps,
what their draw is, electricity wise, from the USB port.
So we'll show that, too.
And let's show the, we're basically gonna focus
on this guy and this guy, since they're the latest.
So let's get into that now.
Okay, so let's test the power supply.
And first, we're gonna test
the main 24-pin connector over here.
Now, there's a couple warnings and notes
that we have to talk about before we begin.
First, you want to employ antistatic methods,
your antistatic strap and mat,
and connect to any earth bonding point,
whatever you need to do to ground yourself
so that we don't damage any of the equipment in here.
And try not to touch any of the components
when you're disconnecting cables.
That's the best way, to be honest with you.
Now, when you're dealing with power, you have to be careful.
So first of all, you want everything disconnected,
your power connection to the computer,
make sure the kill switch is off, if you have one.
And always read the manual, RTM,
when it comes to these power supply testers.
Because there's a certain procedure,
there's a certain order or sequence to these things.
For example, if we want to test this main power connection,
we need to disconnect all the other power connections
from the power supply, except for this main.
So you gotta do that first.
So I've disconnected those.
And that means, optical drives,
hard drives, the CPU, all that stuff, the video card,
all has to be disconnected
before you use this to test the main power connection.
So I've done that.
I have the computer disconnected and the kill switch is off,
and I'm gonna remove the 24-pin-connector,
and plug that into this guy, and we'll do the test.
To remove it, remember there's a locking tab on the side.
So you have to press that in and then pull up.
Make sure you press that locking tab
so you don't damage the connector.
Okay, so I've pulled that out.
And you can see,
this connector is what we were talking about.
This has that separate 4-pin.
So you could test the 20-pin if you wanted to separately.
But I'm just gonna test all 24 pins.
So we'll plug that into the connector now.
Okay, we make sure that that snaps into place.
You wanna make sure it's locked
so that we can start the test.
So I'm gonna plug in the computer
and plug it in the back now
and turn on the kill switch, which is gonna supply power.
Now, remember these are passive devices.
They pull the power from the power supply.
That's one of the reasons
you wanna disconnect everything else
before testing this 24-pin.
So you get a blue screen
and then we gonna hit the test button.
Okay. And we get a another blue screen,
which is good, unlike Windows.
And you get your voltages here.
If you see a red background
on these types of devices, that's bad.
A red background accompanied by beeping,
means that you either still have things connected
to the power supply or something is faulty.
In this case, everything is good.
And you can see the voltages here.
For the 5 volt, it's at 4.9.
For the 12 volt, it's at 11.9.
For the 3.3 volt, it's at 3.3.
And for the others, it's very close as well.
Your -12 is at -11.9.
Your 5 volt standbys at 5 volts.
So we're in good shape.
All the voltages are good here.
And so that's what we want.
We want that blue screen
in order to see if the power supply is okay,
if that 24-pin is okay.
Standard deviation, for example, anything between 4.8 volts
and 5.1 volts or thereabouts, is good.
Normally, you'll be a little bit below.
So 4.9 is fine.
You know, 3.25 is okay. 11.9 is okay.
You wanna be very close to that voltage.
If one is way off, then you wanna make sure
the connector is connected properly.
And beyond that, it could be that one wire is bad.
And we can actually test those wires individually
with a multi-meter.
And we'll show how to do that in a next sub-lesson.
Now, when you're done with your test of your 24-pin,
you wanna make sure you cut the power.
So I've hit the kill switch, and disconnect the power cable.
And you see the power went out,
and that took about four or five seconds.
So you gotta wait a little bit.
Then we can disconnect this guy
and plug him back into the 24-pin,
and then power up our computer normally.
However, I'm gonna move on to testing other ports.
We're gonna test the Molex
and also test the 6-pin connector
and show how that works on here as well.
So we need to leave the 24-pin connector in there
to supply power to the power supply tester
to test those other cables.
So at this point, I'm gonna connect a couple cables.
I'm gonna connect a 6-pin,
which will simulate the video power connection.
And you can do 8-pin also on this tester.
And I'm also going to connect another 6-pin power connector
to test for Molex.
Okay, so I've made my first connection,
and that's the PCI Express video connection.
Now, another word of note here,
when you're dealing with these testing devices,
you can only test one connection at a time,
and nothing else can be connected to the power supply.
The only thing that could be coming outta the power supply
is obviously the 24-pin connector
and the individual connector that you want to test.
In addition, when we're testing the video,
normally that's a red port on the power supply,
as we've shown previously.
And if you have one of these 6-pin or 8-pin connectors,
you wanna connect the red side
to that power supply port, to that red port,
and connect the black side here, if it is black.
So now that we have that done,
we'll hit the kill switch and run the test.
The first test here is for the power supply
for the 24-pin connection.
Press the button again.
And there's our PCI connection.
And it shows it right at 12 volts, 11.9.
And that's what it's supposed to be.
That's the 12 volt connector for PCI.
So we're all good with that.
And I'll kill the power, and we'll disconnect this guy,
and we'll connect a Molex to it.
Okay, so now I've connected a Molex connector here,
and the other end is going to the power supply,
and that's just connecting to one of the 6-pin black ports.
And so we'll do that test now.
Make sure it's connected securely.
We'll turn on the kill switch. Run the test.
And that's the main power supply.
Run the test again.
And there's our Molex connector.
And you can see here, it says MOX.
You know which test you're doing.
PCI means the video.
MOX is a Molex connector, and so on.
You can test all these things.
You have the 5 volt connector at 4.9,
and the 12 volt wire running at 11.9.
So we're within tolerance. Everything is good.
One thing to make note of with these tests
is these testers do not do load testing.
They're just checking the voltage,
which gives you an indicator
of whether or not the connection works,
or if a single wire is bad, or what have you.
So they are not load testers, though.
If you wanna do a load test,
that's a completely different thing altogether.
Generally, you're not gonna have to do that
or know that for the A+ exams.
So having a power supply tester like this is okay.
But keep in mind,
when you're using any of these power testers,
make sure that you're testing one connection at a time,
and make sure you only have one item connected
to the power supply.
That single item that you're testing.
Whether it's the 24-pin connector,
or an individual connector like a PCI,
or an SAT connection for power, or a Molex connector.
Make sure that you have the computer turned off,
the kill switch engaged in the off position,
and have it disconnected as well.
And, of course, antistatic methods, all that stuff.
Make sure you keep this in mind.
And probably, most importantly,
read the manual whenever you're dealing
with any types of power devices.
Very important that you understand what you're doing
before you attempt the test.
And one last note,
be careful when you're dealing with these, guys.
These corners could be really sharp.
And I've cut myself on these in the past.
So you wanna be real careful with these corners,
especially on the 24-pin connectors,
and also those 6 and 8-pin connectors.
Especially if they're brand new, they could be super sharp.
So be careful with that.
And that's about it for the power supply portion of this.
Now, we're gonna get into the USB testing.
Okay, so here we have a USB tester,
and I've plugged it into one of the USB ports here.
You can test any of these ports if you want.
And so what we're gonna do
is we're gonna turn on the computer.
And when we do so, the output shows at 4.97, 4.96.
So it's right around 5 volts.
And that's what we want.
Now, if you wanna check any of these ports, you can.
But generally, they're all gonna be
right around 5 volts for most devices.
So this is a handy tool to tell you
if a USB port has failed or not.
Because individual ports can fail.
It is possible.
You can also check the amps that are being pulled
from the outputs from a USB device.
And so we'll do that as well.
Now, whenever you change any connections,
turn off the power.
So we'll kill that power now.
Wait for that to shut off.
And first we'll use just a basic mouse,
just to show what that'll pull, and connect that guy now.
And we'll hit the power again.
And you can see, is that about 5 volts.
And you can see the draw from a USB mouse is basically 0.
Now, if we were to do something that drew more power,
you would actually see something as far as the amps go.
So now we'll just connect a smartphone.
And plug that smartphone in with the micro USB.
Connect the other end to our tester and start up the system.
And now you can see, again, we're pushing 5 volts.
It's actually a little bit lower now
'cause there is a little bit of a draw.
And it's about .3, .4 amps from that smartphone.
So it can charge the smartphone.
And that's really all you're gonna get from a computer,
somewhere in that range, .2, .3, .4 amps.
If you wanna charge a phone faster and get more power,
you wanna plug it into the AC charger,
especially if you wanna do your adaptive charging,
your fast charging, that kind of thing.
That'll increase the amps,
and then force the phone to charge faster.
As it stands with the USB connection,
it'll charge pretty slow.
But you could see the power draw is very low
for most devices, but it gets higher,
as you use devices that have, say, moving parts,
maybe a webcam, something that does recording,
then your draw gets higher there.
So a little USB testing.
And again, you can test devices, see what the draws,
and then also test each of your USB ports,
just in case you think one is faulty.
And so that's about it for the sub-lesson.