a novice and a broken switch-mode PSU are definitely not a good match and someone is likely to get hurt.

Switch mode PSUs like these if faulty can electrocute you if you touch internal components even after the PSU has been off for a prolonged period.

I do have a vivid memory of being knocked backwards out of a television while trying to disconnect the anode connector from the picture tube. Several other devices can retain a charge, but usually not as bad as a CRT.

Capacitors can give give a nasty shock and can kill if they have enough charge.

perform safety procedures such as discharging all capacitors with an alligator lead and a 10 ohm resistor for at least 2 seconds rather than betting your life that they can't hurt you.

you've been advised not to play with it because half the power supply is at mains potential and even after unplugged has the ability to maintain a charge. even if not lethal can be very nasty.

Eventually you learn about that some day and get a puncture burn.

Only a few need caution, I always tap these with a screwdriver. If i get a bang, I know they were live.

Since you claim to be new to this, you might not know that capacitors can store a charge, just like a battery. They can discharge at the most inappropriate times causing pain and sometimes injury.

Ferden, FYI: a good cap holds a charge. There's a reason that many caps and cap banks employ resistors to act as drains when power is removed. Ignoring this fact can cause equipment damage. If the voltages are high enough, the damage can get personal, as in #12's case.

A few months ago I was working on a DVR power supply board and forgot to discharge the primary Side capacitor, needless to say it punished me for it. It's every bit as unpleasant as getting your fingers across 230vac.

just can't see the point of beating a dead horse

I get it, really. I just said it's rare, and never more than a sparkle. I mean, no need to repeat.

There are software utilities that can show you where power is going and what it's being used for.

Do you know any name?

Oh my. You are a stealer.

Oh my, I only resist a theft. By the way, private property is a theft.

Cant you afford Windows 7 or Windows 8?

Of course I can afford it. Once. What surely I can't afford, nor 95% of humanity, is paying for a program, device or media every time a company feels entitle to ask me money for. Can you image what would be this world if I had to pay Britney Spears for every time I heard one of her songs? Quite often without even my consent?
All that without saying that I certaintly don't like it when Windows imposes a new version (and asks money for it) every three years, nor that holds and enforces a monopoly, nor that it ties the sell of computers with the sell of an OS (itself, of course), nor that it identifies every piece of software, hardware, file (and even users!) with unique identities, nor that Microsoft keeps record of all of that, nor that it uses those records for its greedy and oppressive purposes, nor that you discover a new bug every day, nor the deliberate dumbing down of a software/OS so that a company can ask you money for a number, nor that after uninstalling a software pieces of it (the license info and others) still linger around on your HD, nor the systematic use of trojan and viruses once again with the goal of taking consumers' money, nor that the whole industry is fond of programmed obsolecense (I have boxes full of hardware that DO work, but of course I can't use because old and incompatible), nor that every company imposes the use of proprietary consumables, nor that costumer supports fall nothing short of a scam, nor that companies impose their fantastic view of the world to every user, like, you know, this pretty new "start" page on win8 that you can't get rid of, like those liberal links to "microsoft store" "xbox store" "apple store" "itunes" that you can't delete, like a cute little back-door to the NSA in https...).
Not to mention the mandatory use of English language, the use of countries' public resources to enforce companies' private interests, the use of countries' laws to outlaw the sanitation of protected software and, of course, the fancy new society that social networks and digital communications are shaping...
Do you want to discuss the topic a little further?!?



As for the original problem, to make a little recap: some people say it's a bad idea, even though I didn't understand why:

Pretty much guarantee that's a bad idea, a PC PSU is not a simple switch mode PSU. Standard switch-mode PSUs often can load-share but a PC PSU is a different beast. I recommend don't do it.

Besides there is no good way to parallel them.
You can however use one for the drives with 4 pin connectors (not that I think that would be cutting it).

So the question is: why 2 PSU on 1 MB is a bad idea?



Also, I still don't understand the instructions I got so far:

Use second psu to power video card and maybe power the hard drives/cd rom drives.

All you need to do is to parallel the startup wire, and the ground.
That is often a grey, green or purple wire.

Yes power all the Hds with a second PSU. Do as i explained.

I wired the secondary PSU to power on with just a slide switch by connecting the green wire from the PSU to one of the black(ground) wires with a switch. Just make sure that when powering up, to power up the secondary PSU first, then the primary.

Which of the following setup is the correct one?

1 - Plug the second PSU to the electricity and to some drives but not to the MB.

2 - Plug the second PSU to the electricity, to some drives and wire the second PSU pins 14 and one of 3, 5, 7, 13, 15, 16, 17 ( http://pinouts.ru/Power/atxpower_pinout.shtml ) to the MB (and by doing this to the first PSU as well).

3 - Plug the second PSU to the electricity, to some drives and wire a switch between pins 14 and one of 3, 5, 7, 13, 15, 16, 17 ( http://pinouts.ru/Power/atxpower_pinout.shtml ) of the second PSU (thus not to the MB or the first PSU).

4 - Something else.

 

I get it, really.

Normal people use paper clip: http://aphnetworks.com/tutorials/psu_paperclip_trick

So you take second psu, plug it into wall outlet, plug the video card and drive cables into the videor card and hd/cd/dvd drives. To turn psu on just use the rocker switch on the back of the psu.

Like someone already said:
First turn on the psu that has the paper clip, and that is connected to the video card/hd/cd/dvd.
Second turn on psu connected to the mother board.

 

Ferden, no doubt, there is confusion here. When you started the thread, were you talking about an external power supply or the computer's internal power supply. (I'm reading two different courses at the same time or so it seems.)

 

Ferden, no doubt, there is confusion here. When you started the thread, were you talking about an external power supply or the computer's internal power supply. (I'm reading two different courses at the same time or so it seems.)

I was talking about plugging 2 internal PSUs (actually they are transformers rather than power supplies) to 1 MB.

 

OK. That helps. Suggestion: avoid using the term "PSU" in this case. To many, if not most, a PSU is an external conditioned power supply that the computer plugs into.

Regarding the additional transformers, you risk burning up the motherboard by drawing more power through it than it is capable of withstanding.

I have another question: I believe you said that the RAM was new. Are all slots filled and are they matched (all the same manufacturer and type)?

 

OK. That helps. Suggestion: avoid using the term "PSU" in this case. To many, if not most, a PSU is an external conditioned power supply that the computer plugs into.

"PSU" is the official name, I didn't made it up: http://en.wikipedia.org/wiki/Power_supply_unit_(computer)
It's the name written in the box and stores label them that way.

Regarding the additional transformers, you risk burning up the motherboard by drawing more power through it than it is capable of withstanding.

The PSU doesn't "draw" power from the MB: power to drives simply doesn't transit throw the MB, and today even video cards and CPUs have independent power input (taken directly from the PSU without going through the MB).

I have another question: I believe you said that the RAM was new. Are all slots filled and are they matched (all the same manufacturer and type)?

The RAM banks are identical, they fill half the slots, but they fit the peculiar disposition the MB's manual ask to respect.

 

"...I have a very classic pc: MB, CPU, RAM, pci-ex 16x video card, 3 120mm fan, 2 pci-ex 4x, 1 pci, dvd-rw, front card reader, front usb, screen, printer, keyboard, mouse, 2 gamepad, speaker, headphone with micro and 6 HD (and no, I can't give them up). The PSU is nominally just enough, but it's 6 years old, and if it works under 100% then the math doesn't adds up..."

OK Ferden, I see all of this but I need a little better picture of your configuration.

What is the computer's make and model?

"pci-ex" and "pci" are slots. What is in them specifically?

Is your speaker powered by the computer or does it have its own power? If it's powered by the computer, how many watts is it?

Are the 6 HD's connected to the computer? If so, how are they connected?

Basically, except for the HD's and the undefined PCI's, your computer shouldn't be having power problems.

(And no, I don't work for Microsoft or the NSA.)

 

"PSU" is the official name, I didn't made it up: http://en.wikipedia.org/wiki/Power_supply_unit_(computer)
It's the name written in the box and stores label them that way.



The PSU doesn't "draw" power from the MB: power to drives simply doesn't transit throw the MB, and today even video cards and CPUs have independent power input (taken directly from the PSU without going through the MB).



The RAM banks are identical, they fill half the slots, but they fit the peculiar disposition the MB's manual ask to respect.

Are the RAM sticks next to one another? Do you have the jumper cards (sometimes called "end" cards) in the empty slots?

 

"1. "PSU" is the official name, I didn't made it up: http://en.wikipedia.org/wiki/Power_supply_unit_(computer)
It's the name written in the box and stores label them that way."

Wiki doesn't count. I'm telling you about the terminology that we typically use. Trust me on this. Read the thread. You'll see the confusion. Avoid "PSU" when you're referring to the internal power of the machine. Refer to the internal power supply as "the power supply". That should keep the confusion down.

"2. The PSU doesn't "draw" power from the MB: power to drives simply doesn't transit throw the MB, and today even video cards and CPUs have independent power input (taken directly from the PSU without going through the MB)."

You're showing your lack of understanding. That is my point exactly, the power is drawn through the motherboard and if the board isn't supplying enough power for the load you might draw too much through it if you try to fix the problem by providing more power to the board. Capice?


BTW, how many watts are the fans (each)?

 

your solution.

http://www.amazon.com/Drive-Adapter-Converter-Optical-External/dp/B001OORMVQ

they come as a set but you only need the power supply. enough in that to take a couple amps off the supply.

not unlike this thread, cheap too.

edit:

BTW, how many watts are the fans (each)?

depends on the size, type (sleeve/ball bearing) and if they have inbuilt LED's, usually blue but seen them red / green / white and changing muti-colour ones.

right now you got a thanks from me but not sure if should be

 

your solution.

http://www.amazon.com/Drive-Adapter-Converter-Optical-External/dp/B001OORMVQ

they come as a set but you only need the power supply. enough in that to take a couple amps off the supply.

not unlike this thread, cheap too.

edit:



depends on the size, type (sleeve/ball bearing) and if they have inbuilt LED's, usually blue but seen them red / green / white and changing muti-colour ones.

right now you got a thanks from me but not sure if should be

But getting 6 of them would be quite a stretch.

so next time I go shopping, I argue the factories exploit the workers, sweatshops, the food producers raze the third world, and the retail shops increase price 20x.

Its totally fine to steal, ehm, apply justice by your own means.

when it suits your own laws, you can do it.

 

right now you got a thanks from me but not sure if should be

I'm not sure about the "thanks" either.

 

...private property is a theft.

Do you want to discuss the topic a little further?!?

Nope. I'm out. If you think you're entitled to other people's work and property, then you're entitled to fixing it yourself.

 

Hi everybody,

I finally did it, quite simple after all: I added another (internal) PSU, that now powers some drives. And that's it: no crashes anymore.

At first I opened the first PSU, and, after having duly discharged the capacitors (be sure of that), I noticed they were fine, at least physically. Besides, this thing comes from China, no way those people bought components from Taiwan. That said, changing capacitors doesn't look like something simple either: you don't have a lot of room to work, you still have to spend some money, and go to the shop, and my "welder" is one of the crappy ones (resistance that melts only tin)... So I left the first PSU alone and added the second one. Even though, second thoughts, that was a silly idea too. Being a bit of a maniac, I wanted to fix it to the case, so I stressed the whole pc with my driller... just to discover the PSU's external walls were too floppy to hold its weight. I experimented with various ways to add a metal shelf... just to discover that doing it took me the whole day, and it's not that solid either.

I plugged the PSU to the electricity and some drives, but instead of short-circuiting the green and black cables and using a switch (by the way, this model doesn't have a built-in switch) I paralleled the green and black cables with the first PSU's green and black (and therefore the MB too). It does work, although there's a weird side effect I don't really understand: whenever both PSU are powered, everything works as usual, but if the first one is unplugged, then the second turns on by itself. And as soon as the first one is plugged back, the second turns off, unless instructed otherwise by the MB.

Does anyone have a clue why? Do you really think ALL black cables are interconnected? and that therefore you can deal with one and forget the others?

"2. The PSU doesn't "draw" power from the MB: power to drives simply doesn't transit throw the MB, and today even video cards and CPUs have independent power input (taken directly from the PSU without going through the MB)."

You're showing your lack of understanding. That is my point exactly, the power is drawn through the motherboard and if the board isn't supplying enough power for the load you might draw too much through it if you try to fix the problem by providing more power to the board. Capice?

Nah, I meant the power that feed the DRIVES, you know, those plugged by these:

http://en.wikipedia.org/wiki/File:Molex_female_connector.jpg
http://en.wikipedia.org/wiki/File:SATA_power_cable.jpg

doesn't comes from the MB but directly from the PSU. The MB of course draw power from the PSU. Your sentence implies:

household electricity -> PSU -> MB -> drives
or
household electricity -> PSU -> MB -> PSU -> drives

while it's:

household electricity -> PSU -> drives
+
household electricity -> PSU -> MB



@ faley: sorry I don't answer the other questions, but apart for not having any proof you don't actually work for the NSA, I think the case is solved. Thank you by the way.

your solution.

http://www.amazon.com/Drive-Adapter-Converter-Optical-External/dp/B001OORMVQ

This cable serves only 1 hardware, if you need many, then you go for an internal PSU... that I already have.

so next time I go shopping, I argue the factories exploit the workers, sweatshops, the food producers raze the third world, and the retail shops increase price 20x.

Its totally fine to steal, ehm, apply justice by your own means.

when it suits your own laws, you can do it.

I would add that capacitors are crappy too, and that's not fair.

 

Hi everybody,

this reminds me of a cat with nine lives, now to deal with the pixels on the screen

I plugged the PSU to the electricity and some drives, but instead of short-circuiting the green and black cables and using a switch (by the way, this model doesn't have a built-in switch) I paralleled the green and black cables with the first PSU's green and black (and therefore the MB too). It does work, although there's a weird side effect I don't really understand: whenever both PSU are powered, everything works as usual, but if the first one is unplugged, then the second turns on by itself. And as soon as the first one is plugged back, the second turns off, unless instructed otherwise by the MB.

got a case of the flip flops there. none of the power rails should have been joined between PSU's

This cable serves only 1 hardware, if you need many, then you go for an internal PSU... that I already have.

does your vocabulary include assumption? its serves as many hardwares as what the supply can deliver.

[FX: grabs, 5 x 256gb ssd's, plugs into said power adaptor, plugs into usb ports, checks drives]

yup all working, though in all fairness, hard drives draw a bit more current (~5vdc/12vdc @ ~0.7aH each rail) that still gives you 2 and possibly 3 off the ONE adaptor