Dead PC? Rapidly blinking diagnostic led, no fans or anything else

moosepig

Member
Hi all,

First time poster on these forums so please forgive me if this has been covered elsewhere.

My 2-year-old PCS supplied desktop has apparently died, powering it on merely results in a rapidly blinking red LED on the multi-card reader. Opening up the case shows that the green LED next to the diagnostics card and the two buttons on the diagnostics card itself are also blinking rapidly. There is no other activity anywhere.

I tried unplugging everything but same result.

When I power on the PSU, there is no voltage on the motherboard 12v connectors (EATX12V), and the 24-pin connector (EATXPWR) has only one of its 5V lines powered up (the 5V standby) and 2.3V on one of the other pins (the PSON# pin). Is this normal? I suspect I may have a dead PSU but I have no idea what pins should be powered up before the mobo gives the go-ahead (I believe that's how these things work these days!)

Over the last few months, odd things have been happening. First, sleep mode stopped working overnight Consistently thereafter, every time I tried to use sleep mode the PC would power down completely, leaving me with the "not shut down properly" messages on power-up. More recently, the screen has been flickering, particularly while playing Just Cause 2. Could that be a failing PSU?

If anyone can help shed any light on what's gone wrong here I'd be most grateful. I'm techie, but not at this level.

The system is: Asus P6T WS Pro motherboard, Intel i7-920, 6GB Corsair Tri-DDR3 1600MHz RAM, FSP Everest 800W Quiet quad rail PSU, Coolermaster Sileo 500 case, 1GB ATI Radeon HD5750 graphics card, 4x1TB SATA HDD (arranged as 2x2TB RAID1), Windows 7 Professional 64-bit, Blu-ray writer, DVD rewriter, wireless N card, multi-card reader.

Many thanks,
Moosepig
 
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Wozza63

Biblical Poster
this may have something to do with the power supply, it is enough although you got the much cheaper power supply which are more likely to cause what possibly happened here, i think the mem card reader is a seperate lead and therefore would be working fine, meaning that there is something wrong between the motherboard and the PSU, have you tried reseating these cables?

if you dont feel confident about doing this then you can phone PCS up in the morning and they would be happy to help, although they will not replace items free of charge, i think they will offer you a new part at a price if you wish to buy it from PCS
 

moosepig

Member
Thanks for a rapid response :) Tried re-seating all the mobo power connectors (and giving all the others a shove and removing the graphics card) to no avail - flashyflashyflashy goes the LED. The power supply does smell a bit funny - a bit like electolytic capacitors that we used to blow up at school, a sort of acrid smell, and the house smelt a bit like that when I got home today. Incidentally I've corrected the pin numbering on my original post, I was looking at the plug but using the mobo socket pin-out, the 5V standby line has around 4.7V on it, and the PSON# line has around half that (not that surprising) with no voltages anywhere else.

PC was working fine last night, shut it down at around 1am, didn't look at it this morning, by 4.30pm it's carked it. It was already flashing when I went to turn it on, so it hasn't gone phut on switch-on or something like that, and it wasn't under load when it went wrong.

I just hope it's not the motherboard that's up the spout!

Thanks again,
Moosepig
 

Wozza63

Biblical Poster
well PCS know much better than me, you are much better off contacting them, i would recommend not touching it until then if you are getting funny smells, leave it unplugged at the power as well
 

moosepig

Member
Thanks. I've emailed PCS but am trying to minimise downtime if I can.

Tried shorting the PS-ON pin to ground, nothing. That is supposed to power up the PSU if it's working, so a bit more evidence in favour of a carked PSU. I have a borrowed unused ATX power supply which behaves correctly when I short PS-ON to ground (spins up its fan for one thing), I don't get anything at all from the Everest. I'm a bit reluctant to plug the borrowed PSU into my mobo as it only has a 20-pin power plug (so must be pre-ATX v2.0).
 

Wozza63

Biblical Poster
i cant really help you with your problem, i dont want to be the cause of something bigger, id leave it unplugged and dont do anything because that could make it worse
 

moosepig

Member
Yeah, I'm far too wary of weird incompatibilities to try anything more until I hear back from PCS. I didn't know until tonight how many versions of the ATX PSU "standard" there are!

Cheers,
Moosepig
 

moosepig

Member
Update: spanking new corsair power supply fitted, everything back as it should be - even the sleep function works again. This was clearly a progressive failure over a period of several months, so thank heavens for protection circuitry and failsafe designs. Thanks :)
 
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