PSU failure?

[calidar]

I've had this issue twice now, namely my system wont power on. This first time I simply just turned it off via the switch at the back unplugged it from the wall and left it for a while, then it powered on as normal, except for the fact that it loaded into the standard bios settings (not the overclocked ones). This time that hasn't worked. I should stress that both times this has happened has been after unplugging it from the wall. The next time I try to start it, it just doesn't turn on which is why the first time I put it down to just me forgetting to press the switch at the back, or something along those lines.

I removed the side panel to check for any wires that were obviously not where they should be and could not see any. I did however smell a very very faint whiff of electrical burning (although this may be normal I just don't know.)

Hopefully this is enough information.

What should I do.

Thanks.

[Ben @ Scan]

Hi calidar

We are sorry to hear of the issue with the system, unfortunately we cant access your records through Hexus please either email us through your original query for the system or drop us an email to systemsupport@scan.co.uk with the Build and Invoice number

Regards

Ben

[calidar]

Have done so.

[Thorbog]

Calidar, did it turn out to be the PSU at fault?

I've just emailed support about a similar problem.

My PC suddenly started refusing to turn on. I'd turn it on at the mains switch and then on the PSU switch, but pressing the case button would result in a whole lot of nothing happening!

However about a minute after turning it on at the mains/PSU it would suddenly turn on. I found that by turning on the mains/PSU and waiting a minute, it would fire up with one press of the case button.

I've run mine in the non-OC settings since it was new so can't comment on that. The PC is otherwise working perfectly.

Until today when I smelt burning!!!! Definitely not a normal smell. So I shut it down. An inspection didn't reveal anything obvious with the PSU but I ain't gonna use it again!

[Bambooz]

To me (fixing various electronics as a hobby), this sounds like the 5VSB part of the PSU is toast (or at least on its way of frying). I see this a lot on Fortron-Source based PSUs with crappy capacitors. Then again, saying "fortron-source with crappy capacitors" is kinda redundant.. lol

[Thorbog]

I am completely clueless about electronics so I don't understand any of that!

In layman's terms what exactly is happening that it takes a minute of being "live" before it will turn on?

Just curious. Is it because it is "warming up" or something?

[Thorbog]

Well it is toast now! Won't work at all! I assume that being a modular type it would be very easy for a novice like me to swap out? Just unplug all the connectors, unbolt the thing from the chassis, bolt on a replacement and plug the connectors back in?

Doesn't matter which sockets each connector goes in right?

As opposed to going through the malarkey of sending it to Scan and back (it is just over a year old so under rtb warranty now).

I guess the direct replacement of the ax 850 psu is the 860 model as I can't see the 850 anymore.

[calidar]

Calidar, did it turn out to be the PSU at fault?

I've just emailed support about a similar problem.

My PC suddenly started refusing to turn on. I'd turn it on at the mains switch and then on the PSU switch, but pressing the case button would result in a whole lot of nothing happening!

However about a minute after turning it on at the mains/PSU it would suddenly turn on. I found that by turning on the mains/PSU and waiting a minute, it would fire up with one press of the case button.

I've run mine in the non-OC settings since it was new so can't comment on that. The PC is otherwise working perfectly.

Until today when I smelt burning!!!! Definitely not a normal smell. So I shut it down. An inspection didn't reveal anything obvious with the PSU but I ain't gonna use it again!

No it was the motherboard. We replaced the PSU onsite and when that didn't work the engineer sent it back to scan to be examined.

[Thorbog]

Hmm that is interesting.

I haven't had any mobo issues though and I have had multiple Corsair PSU failures (this was the longest I'd had a Corsair PSU last) including one like this where one day it just refused to turn on.

I remember a few days ago it also arced quite noticeably when I turned it on at the switch and I had never seen that before.

My money is on the PSU again. I wonder if yours was the PSU and it also damaged the MOBO?

I am curious as to why I have had so many PSU failures on my Scan systems. I even have my tower on wooden blocks to raise it off the floor for more ground clearance and the dust filter was as clean as a whistle. I don't run it overclocked and the machine cruises on most games with the GPU fans nice and quiet so it isn't running hot or anything.

I had loads of PC's from MESH before with no issues. I do notice though that my Scan PC's have had less head room on the PSU's. The MESH units had way larger PSU's than were needed (you could have upgraded them to SLI without changing the PSU) where as my Scan systems have simply had "enough".

I am no electrical expert but I wonder if running them near their maximum loads a lot can reduce the life span? Would a 1200 have been more reliable than an 850?

I had considered there being an issue with the electrical supplies in my area but then as I said I've not had issues with all my other PC's and back in February I replaced my surge protected multiplug with a brand new one and put the old in another room so that kind of rules out my cables.