Can a bad PSU damage my motherboard?

[AD-15]

hello,

I posted a while back about some problems I've been having with my PSU.

http://forums.hexus.net/hexus-hardwa...-problems.html

Basically, I have not managed to RMA it, and still have it in my PC.

I still have to flip the switch several times to get my PC to start.

Is there any chance this rapid on/off switching can damage my motherboard? I'm assuming there is power being supplied when the switch is in the on position.

The entire system is new (and obviously expensive) apart from the Tagan PSU. I don't want to fry the lot.

Thanks for any advice!

[ajones]

I'm not the only one around here whos had to replace mobo/cpu when a cheap PSU has gone west. Good quality PSUs however (which I believe Tagan produce) usually die gracefully without frying your PC.

Bottom line though, IMHO, if you have concerns about your PSU, then replace it.

[shaithis]

A dodgy PSU can fry a lot of things, or nothing at all. It's pot luck.

You just need to ask yourself 1 question...

"Do you feel lucky, punk?"

Change the PSU ASAP....the fact your turning it on/off several times to get it going leaves me thinking you shouldn't even turn the PC on again until you have replaced it.

[Andeh13]

Go for a corsair HX520 (or similar quality name brand) & you'll never have to worry about this sort of thing again!

[BUFF]

Tagan are a decent quality name brand though.
despite that you will get failures when you make (or resell) enough of anything.

[CAT-THE-FIFTH]

TBH,I would get a new PSU. There are plenty of decent units for under £50 currently. It is not worth risking new components with a PSU which is failing.

[malfunction]

@OP Your spec says you have a Corsair 620HX but your older thread says a 380W Tagan... What are you powering with the Tagan?

Oh and +1 for replacing it; it's not worth risking your whole system for one component if that component is in doubt. That said I'd probably do an 'open air' test with the components all out of the case (but adequately insulated, etc) in case something is grounding out on your case.

[Andeh13]

Just to clear up, i didnt mean to sound like i was implying that Tagan are a poor brand, never had any experience but if the above lot say its a quality brand, there is no need to think otherwise! Was just emphasising the need for a quality PSU.

[peterb]

In a word, YES (a faulty PSU can damage your motherboard.

However, having re-read your original post, I'm not clear in my own mind what the problem is. Do you mean that the PSU computer won't soft start (using the button on the front) unless you flip the on off switch a few times? If so, and given that the same operation at the wall socket doesn't have the same effect, I would think that the little rocker switch on the PSU is faulty, and therefore flipping it is unlikely (from what you have said) cause damage by power surges.

The difference between a good PSU and a poor one include the way it protects itself (and the equipment connected to it) in the event of a fault. A good one will monitor the output voltage, and the current drawn, and shut itself down in the event of a fault, hopefully in time to prevent damage to the components it is powering. These fail safe mechanisms require more complex ccts, and testing, which is one reason why they cost a little more.

[AD-15]

hello,

Thanks for your advice everyone.

The system spec I am currently powering with the Tagan 380W is as follows:

-Intel E2180
-2GB DDR2
-ATI 2600
-Audigy soundcard
-2 optical drives
-4 case fans

I did a PSU calculator check before I put the system together, and it was fine. I am not getting any stability issues either, apart from some BSOD's when putting the system in sleep mode, or performing specific actions. They seem to be software related though (from my research on the internet).

I've done all sorts of tests, nothing fixes the problem. I've also made sure the thing is properly grounded, but it makes no difference.

However, having re-read your original post, I'm not clear in my own mind what the problem is. Do you mean that the PSU computer won't soft start (using the button on the front) unless you flip the on off switch a few times? If so, and given that the same operation at the wall socket doesn't have the same effect, I would think that the little rocker switch on the PSU is faulty, and therefore flipping it is unlikely (from what you have said) cause damage by power surges.

When the PSU 'rocker' swtich is in the off position, and is then switched on, most of the time the PC will not soft start. Sometimes it works, sometimes nothing happens. Sometimes it starts (lights, fans spinning etc) but only for a fraction of a second, then it turns off again. To get it to swtich on properly, I must then rapidly switch on/off the PSU by the rocker switch several times, and then hit the case power button. The switch on the wall socket has absolutely no effect. If I leave the rocker switch in the on position on the PSU, it will always start fine, no matter what happens at the wall.

So yes, you understood my original post correctly.

I too thought the switch would be faulty (mechanically), but if this was the case, then why is it the system sometimes starts for a split second, and then switches off again?

The difference between a good PSU and a poor one include the way it protects itself (and the equipment connected to it) in the event of a fault. A good one will monitor the output voltage, and the current drawn, and shut itself down in the event of a fault, hopefully in time to prevent damage to the components it is powering. These fail safe mechanisms require more complex ccts, and testing, which is one reason why they cost a little more.

That's some excellent advice, thank you. In case I do end up having to purchase another PSU, what sort of features should I be looking for to guarantee the unit has these 'fail-safe' mechanisms (other than an extortionate price )?

Thanks!

[malfunction]

When the PSU 'rocker' swtich is in the off position, and is then switched on, most of the time the PC will not soft start. Sometimes it works, sometimes nothing happens. Sometimes it starts (lights, fans spinning etc) but only for a fraction of a second, then it turns off again. To get it to swtich on properly, I must then rapidly switch on/off the PSU by the rocker switch several times, and then hit the case power button. The switch on the wall socket has absolutely no effect. If I leave the rocker switch in the on position on the PSU, it will always start fine, no matter what happens at the wall.

I went to the doctor the other day,
I said "It hurts when I do that"
he said "Well don't do it"

Seriously - why do you need to use the rocker switch at all?

[AD-15]

To be honest, because of these problems, I simply don't use it most of the time.

But, I wanted to see whether damage had already been done to my motherboard, and more importantly, whether there could be a more serious issue with the unit.