Is there any way to test a power supply?

[Daffy D]

So the kids computer had been playing up, sometimes not starting and very slow.

 

Had dig around and replaced the power supply which seemed to fix the problem.  

 

Running a scan on the HDD threw up several faults, so replaced that also and that seems to have solved the problems.

 

Thing is I'm not sure if the original power supply was actually faulty, could have been the bad HHD all along, so reluctant to throw away what might be a perfectly good unit I wonder if there is a way of testing the power supply unit, without installing it in a computer, to make sure, if it is faulty or not. 

 

[JaiMaai]

You could do very basic tests on voltage but that most likely only be able to prove it is bad.  Even if the voltages measure ok, you would need to find a way of testing it under load to check if it is actually "good".

[Crossy]

Here is a good place to start.

 

 

I tend to put "suspect" bits on the shelf until I need one, then fire it up, if it works, great, if it doesn't go shopping ????

 

[colinneil]

Easy way to test if you have power, stick your finger in the socket, if your hair stands on end you got power.????

[Daffy D]

Thanks crossy I know about the paper clip test.

 

The computer did fire up and the HDD did work so the power supply does work, but as JaiMaai mention really need to test under load.

 

Think I'll just bin it, not worth messing about hoping it might be alright.

 

colinneil - The finger (wet) in the socket test was my first thought but unfortunately that only works on mains voltage so ruled that out.

 

crossy - I also used to keep old suspect bits of gear but found I would never use them because they were "suspect". realized it was a waste of time replacing  a bad unit with a dodgy one, so now I just cut off the wires with the various plugs on them and any switches and sockets that might come in useful and put the rest out for our local dustbin diving recycle man. 

[bendejo]

18 hours ago, colinneil said:

Easy way to test if you have power, stick your finger in the socket, if your hair stands on end you got power.????

There was a fellow on here a while back who said he would give this method a try.

We haven't heard from him since.

 

 

[Daffy D]

4 hours ago, bendejo said:

There was a fellow on here a while back who said he would give this method a try.

We haven't heard from him since.

 

 

Guess it must have worked - Shame he didn't stay around to use it   

[Daffy D]

Looks like there is a safer way of testing:-

https://www.lazada.co.th/products/2024-i10100120-s12650690.html?spm=a2o4m.searchlist.list.17.ad377bb9KfOsWm&search=1

 

All this modern technology stuff take the fun and excitement out of the good old finger test 

[wgdanson]

8 minutes ago, Daffy D said:

Looks like there is a safer way of testing:-

https://www.lazada.co.th/products/2024-i10100120-s12650690.html?spm=a2o4m.searchlist.list.17.ad377bb9KfOsWm&search=1

 

All this modern technology stuff take the fun and excitement out of the good old finger test 

I know it is only a couple of hundred baht, but how often would you use it? How many times in the last 5 years have you suspected your power supply to be faulty?

[wgdanson]

23 hours ago, Daffy D said:

So the kids computer had been playing up, sometimes not starting and very slow.

 

Did you ask them what software they had downloaded and installed, or what settings they had altered?

[Daffy D]

Good point about the amount of use a tester would actually get.

 

At the moment I have possibly a faulty power supply which I can just throw away or spend a couple of hundred baht on a tester and find it is not faulty after all thereby, for the couple of hundred outlay saving about 1000 Baht on buying a new one.  

 

OR testing shows the power supply to actually be faulty so would throw it away, in which case I could have thrown it away originally without spending the couple of hundred baht on a tester which I probably will never use again. 

 

Argggg!! These kind of decisions are way above my paygrade.

 

I keep a pretty close eye on the kids computer, the problem here was almost certainly the faulty hard drive which showed up a whole bunch of faults when checked.
 

[millymoopoo]

Why not just plug the 'faulty' power supply back into the 'now repaired - HDD replaced' PC and see if the original fault starts again, if so it's a dud and chuck it, if not then fault was probably HDD.

[reallybigken]

I'm a electrical engineer. If your computer's performance slows, it has nothing to do with the power supply. If thing stop working or it doesn't boot (post) then the power supply could be one of the reason, but it would be the only one.

 

Performance issues usually relate to software, and those components that directly interact with the software (like hard drive, memory, CPU and Graphics card).

 

If you are running Microsoft Windows there are cases were it gets slower over time as you install and/or remove software. I would always run a virus scan first, then hard drive check/scan, and then performance scan (My virus softeare includes a performance scan). Once every few years I actually re-install the operating system to give it a fresh start.

 

Note: if you ever see a hardware error on your HDD.. back it up and replace it A.S.A.P. Modern HDD have built in error correction systems, and will correct as may faults as it can. If you see a HDD ether directly (reported by the operating system), or after running a scan, it means your HDD has corrected everything it can and now you need to do something.

 

I hope this helps.

 

[atyclb]

58 minutes ago, reallybigken said:

I'm a electrical engineer. If your computer's performance slows, it has nothing to do with the power supply. If thing stop working or it doesn't boot (post) then the power supply could be one of the reason, but it would be the only one.

 

Performance issues usually relate to software, and those components that directly interact with the software (like hard drive, memory, CPU and Graphics card).

 

If you are running Microsoft Windows there are cases were it gets slower over time as you install and/or remove software. I would always run a virus scan first, then hard drive check/scan, and then performance scan (My virus softeare includes a performance scan). Once every few years I actually re-install the operating system to give it a fresh start.

 

Note: if you ever see a hardware error on your HDD.. back it up and replace it A.S.A.P. Modern HDD have built in error correction systems, and will correct as may faults as it can. If you see a HDD ether directly (reported by the operating system), or after running a scan, it means your HDD has corrected everything it can and now you need to do something.

 

I hope this helps.

 

 

 

i had performance issues, slowdowns, etc. turns out my power supply was good but not watt rated adequately to handle the harware connected. power hungry gpu, multiple hard drives, etc .  upgraded the power supply and all is well.  removed ps works great in a different computer with less power demands

[Jingjock]

On ‎1‎/‎11‎/‎2019 at 4:29 AM, bendejo said:

There was a fellow on here a while back who said he would give this method a try.

We haven't heard from him since.

You mean that you not go to the funeral NICE

[Daffy D]

Running slow was just one of the symptoms but on reflection that was probably just in comparison with my own computer which has a better CPU and SSD and would boot up in about 25 seconds compared to the kids taking over a minute.

 

The real problems that made me suspect the power supply was that sometimes the thing would not boot up at all or it would boot up but the monitor would not switch on.

 

By replacing the power supply seemed to fix these problems.

 

Having the computer seemingly running OK I did the regular updates and virus scans but when it came to do a Macrium back-up got disk error fail. Macrium recommended ckdisk scan which showed no disk fault.  

 

I then took the kids disk plugged it into my own computer and ran Hard Disk Sentinel and Crystal Disk scan both of which showed up several faults on the disk. 

 

I replaced the kids HDD with a new one and after several days it still all seems to be working just fine now.

 

Still don't know if the power supply is good or not. Could have had double fault power supply and HDD.

 

The replacement power supply is one that was knocking about and a lower rating than the one I took out so that should not be a problem. As suggested easiest way to check the power supply now the computer is working OK is to swap the "replacement" with the "original" and see what happens.

 

Oh! Happy Days  

 

 

 

 

 

 

 

[Daffy D]

Update:

So I restored the original the power supply, which I thought was faulty, and it's been running fine for a couple of days now so seems the only fault was with the drive, nothing to do with the power supply.

All's well that ends well.

 

Some additional info for replacing drive "D" without having to reinstall the whole operating system and your settings, programs and apps.

 

An internet search suggests making a clone of the old onto the new. Well that did not work for me, presumably because of the faults on the old drive.

 

Trying to make a backup with Macrium also failed because of "drive read error" from the old drive.

Fortunately Macrium has an option "ignore bad sectors when creating images" so was able to make a full backup with possibly some bad sectors. I then restored that backup onto the new drive and Yep! it works. Don't know about any missing data from the bad sectors, seems to be working just fine.

 

So seems an easy way to upgrade your old HDD to a new SSD without having to reinstall everything is just to make a full image backup of the old disk and then restore that onto the new disk.

 

Does not seem to matter if the new disk is smaller than the old, as long as the data on it is less than the size of the new disk it should work.

 

In my case the old disk was a 350Gb HHD and the new a 250Gb SSD and the data was less than 100Gb so still plenty of room on the new SSD.

 

Happy Ducky 
 

 

 

 

 

[reallybigken]

On 1/10/2019 at 6:15 PM, Daffy D said:

Looks like there is a safer way of testing:-

https://www.lazada.co.th/products/2024-i10100120-s12650690.html?spm=a2o4m.searchlist.list.17.ad377bb9KfOsWm&search=1

 

All this modern technology stuff take the fun and excitement out of the good old finger test 

This is just a voltage tester. It doesn't test the supply under load. you could to the same with a volt meter. This just makes it easier (witch is good).

[reallybigken]

On 1/11/2019 at 9:51 PM, atyclb said:

 

 

i had performance issues, slowdowns, etc. turns out my power supply was good but not watt rated adequately to handle the harware connected. power hungry gpu, multiple hard drives, etc .  upgraded the power supply and all is well.  removed ps works great in a different computer with less power demands

Modern computers are very complex and there a many available options.

 

I was assuming a correctly configured computer that had been running correctly before.

 

Modern graphics hardware (Nvidia, AMD, Intel), typically, contains two different sets of video control electronics (in the same hardware). One is usually VESA (video electronics standards association -- vesa.org) compliant or based on a well know, older graphics system (I will refer to the as "low performance" graphics) . The other is a proprietary "high performance" graphics system.

 

When you install an operating system, or the computer is booting, it uses the "low performance" graphics to display information on your monitor. Once everything is running it may load the driver for the high performance graphics system. The "low performance" system uses a lot less power than the "high performance" system.

 

Your computers can work fine with the lower performance graphics system and maybe able to play games, with significant diminished performance .

 

I'm guessing, on your system the "high performance" system determined that there wasn't enough available power to run in "high performance" mode, so it left the "low performance" graphics active. It is possible that it only used part of the "high performance" system, or slowed the clock in order to use less power (although I have never heard of this)

 

1) The first case, the power supply section connected to your graphics hardware could have been dropping out when your system tried to use the "high performance" graphics system, and then the "high performance" graphics system detected a low supply voltage and when back to "low performance" graphics. Though I thick this is less likely as most power supply's will shutdown if this occurs.

 

2) The second case is were the computer tries to use the "high performance" graphics system and the load on the supply causes the voltage to dip just enough for "high performance" graphics system to think there is a low voltage condition and it automatically goes back to the "low performance" graphics system.

 

I have actual seen both. But with the first case the whole system shut down. With the second case there was a momentary blanking of the screen and then it would continue, but running much slower. Newer system may make the transition smother and they may not be a blanking of the screen.

 

Also, the power supply outputs may start to sag over time and heat causing the second case to occur more often.

 

There are also possibility for a combination of all these factors. There are so many options for CPU's, Power Supply''s, Motherboards, graphics ..... etc.

 

It real comes down to debugging the most common failures first and them move to the less common ones. Hard-drives is a good starting point (non SSD's). It a mechanical device, and "usual" fails before the electronics.

 

I hope this help.

 

 

[atyclb]

1 hour ago, reallybigken said:

Modern computers are very complex and there a many available options.

 

I was assuming a correctly configured computer that had been running correctly before.

 

Modern graphics hardware (Nvidia, AMD, Intel), typically, contains two different sets of video control electronics (in the same hardware). One is usually VESA (video electronics standards association -- vesa.org) compliant or based on a well know, older graphics system (I will refer to the as "low performance" graphics) . The other is a proprietary "high performance" graphics system.

 

When you install an operating system, or the computer is booting, it uses the "low performance" graphics to display information on your monitor. Once everything is running it may load the driver for the high performance graphics system. The "low performance" system uses a lot less power than the "high performance" system.

 

Your computers can work fine with the lower performance graphics system and maybe able to play games, with significant diminished performance .

 

I'm guessing, on your system the "high performance" system determined that there wasn't enough available power to run in "high performance" mode, so it left the "low performance" graphics active. It is possible that it only used part of the "high performance" system, or slowed the clock in order to use less power (although I have never heard of this)

 

1) The first case, the power supply section connected to your graphics hardware could have been dropping out when your system tried to use the "high performance" graphics system, and then the "high performance" graphics system detected a low supply voltage and when back to "low performance" graphics. Though I thick this is less likely as most power supply's will shutdown if this occurs.

 

2) The second case is were the computer tries to use the "high performance" graphics system and the load on the supply causes the voltage to dip just enough for "high performance" graphics system to think there is a low voltage condition and it automatically goes back to the "low performance" graphics system.

 

I have actual seen both. But with the first case the whole system shut down. With the second case there was a momentary blanking of the screen and then it would continue, but running much slower. Newer system may make the transition smother and they may not be a blanking of the screen.

 

Also, the power supply outputs may start to sag over time and heat causing the second case to occur more often.

 

There are also possibility for a combination of all these factors. There are so many options for CPU's, Power Supply''s, Motherboards, graphics ..... etc.

 

It real comes down to debugging the most common failures first and them move to the less common ones. Hard-drives is a good starting point (non SSD's). It a mechanical device, and "usual" fails before the electronics.

 

I hope this help.

 

 

 

how about just adding up the total wattage for powered components and selecting an appropriate power supply?  i'd likely go a bit higher though for a margin of safety or should higher wattage components be added in future. the premium brand modular power supplies usually do fine without needing to choose 1 step higher wattage

Edited January 15, 2019 by atyclb