No power despite new PSU

[finnrogers]

My PC decided it wasn't going to work anymore a few weeks ago. Last time it was known to be working it was shut down normally with no apparent problems. When I went to power it up the next day, nothing happened when I pressed the power button. No fan activity, no harddrives whirring up, no beeping, zip, nada, nowt.

My initial thought was to change the fuse in the power lead in case a surge had knocked that out (although unlikely since the PC is connected to a surge-protected 6-way mains extension) - this didn't do anything.

So after a couple of weeks I got a new power supply - got a 550W jobby which ticked all the boxes for my requirements. Fitted that and tried to fire up but still not even a cough or a splutter (no activity what-so-ever).

So it's back to the drawing board AGAIN (see previous posts for my tale of woes) - The motherboard is now the 4th MSi Neo 2 Platinum motherboard that has been used in this rig - I've always stuck with the same one because my HDDs are in RAID 0 configuration and I don't want to lose the data on them (I know I should have it backed up but I cba backing up 320gb of videos onto 4.4Gb DVD-Rs!).

I'm litterally at the end of my tether with this rig - it's been nothing but problematic apart from the 6 months prior to this current problem.

Any advice on what might be the problem and resolutions would be much appreciated. Thank you.

[shadowmaster]

What psu did you buy? (Make, model)

[finnrogers]

It's a SumVision PowerX one - Cheap I know and I know I shouldn't skimp on the PSU but this is for fault finding purposes only and it should certainly be ample to power up the rig with no HDDs, DVD writer and fans attached to it (so just mobo, cpu, gfx and ram).

[shadowmaster]

It's a SumVision PowerX one - Cheap I know and I know I shouldn't skimp on the PSU but this is for fault finding purposes only and it should certainly be ample to power up the rig with no HDDs, DVD writer and fans attached to it (so just mobo, cpu, gfx and ram).

I would go so far to say that even for 'fault finding purposes' a cheap psu is not recommended. It could end up causing more problems.

However it could be the motherboard that's causing problem, the only way to confirm is to get a proper psu and test it again. Can you borrow one from a friend?

Also what psu were you using before?

And do any motherboard lights come on when you turn the psu on?

[finnrogers]

Nope, no lights (not that there is any AFAIK) - Can't borrow a "proper" PSU, but seriously, it's cheap but it's up to the job... it meets all the power requirements in terms of voltage, rails, etc... and I'm not overloading it at all so I'm pretty sure it's not the problem.

My previous PSU was a Enermax Liberty 400W.

[!TIMMY!]

Well if you have no way to test the new psu, it could be faulty. I know its a small chance. You could buy one of these and see it the PSU would power up e.g. fans.

[peterb]

Odd that not even the PSU fan spins. Assuming you have checked the mains fuse in the plug (and there is power to the mains socket) then you need to check that the power button is actually working - and plugged in correctly to the mobo. If you can add some load to the PSU, you can short the appropriate wires together on the PSU output to force it to start. (PS start and ground - see the link) Car indicator bulbs (or the old style headlamp bulbs) make good dummy loads.

http://www.helpwithpcs.com/courses/p...nc-pinouts.htm

Or if you have another computer, try the PSU ion that.

If the pSU is OK, then it is back to standard fault finding - strip it down, start with minimum components, and build it up part by part.

[GoNz0]

Well if you have no way to test the new psu, it could be faulty. I know its a small chance. You could buy one of these and see it the PSU would power up e.g. fans.

or use a paper clip http://www.metacafe.com/watch/729606...er_supply_psu/

[finnrogers]

Thanks, I'll try the paperclip trick to make sure the new PSU works. Will be very surprised if it doesn't...

[finnrogers]

yep - both old and new PSUs work fine using the paperclip... can't see any problem with the power switch on the case so I'm thinking dead mobo?

[dangel]

Did you plug in the 12V cpu line? That one always gets me!

[finnrogers]

yeh definately all plugged in fine. Tried both PSUs last night, fiddled with the power switch too (actually pulled it off the front panel of the case - it was just attached by a clip) made sure this was definately plugged in properly onto the motherboard.

Incidentally, I plugged all my other components in too and using the paperclip method they fire up with the PSU with no problems so at least I know they are not fried.

[dangel]

Follow the lead from the power switch to the motherboard - identify which two pins it connects to and bridge these with a screwdriver (very carefully) to see if it powers up normally?

[GoNz0]

can also try a bios reset, ive only seen it happen once due to bad bios though

[peterb]

can also try a bios reset, ive only seen it happen once due to bad bios though

It won't boot, so he can't do anything with the BIOS. (Except replace it - if it is plug in). And even if the BIOS was corrupted, there should be some activity, even if it is only fan operation.

[finnrogers]

Follow the lead from the power switch to the motherboard - identify which two pins it connects to and bridge these with a screwdriver (very carefully) to see if it powers up normally?

Dangel, thanks, I'll give that a try. It hadn't occured to me to try that actually but still, I don't really hold a great deal of hope on this working.