My new PC is cursed!

New theory:

Inrush current. At power-up a PSU pull a boatload of current to charge up it's caps. This is why I have to plug/unplug/plug/unplug my powerbrick on airplanes because a single plug in trips the outlet overcurrent, but multiple plugins will charge up the caps to the point that it will no longer trip the outlet OCP.

So now we have a single 12v rail pulling probably 40+ amps on a 15A household line...this drops the voltage low enough to trip the PSU undervoltage protection circuit. It doesn't happen when fewer things are plugged in because the extra things slow the cap charge by bleeding charge resulting in a higher inrush current.

The older, 6-rail, supply doesn't do this because the individual rails are smaller (30A) so their inrush current is much smaller...

Test for this is replacing the AX1200 with the AX1200i which has a massively lower inrush current spec. Picking one up tonight...will give it a whirl tomorrow sometime.
 
New theory:

Inrush current.
I said this like 2-3 times already now... :(

My corsair (I said 1150i previously I think but it's probably 1200i yeah) does this little tick with a relay when you start it up. That's the inrush current limiter; it has a resistor in series with the A/C socket and the bigass line filtering caps to let the caps fill up gradually, then the relay bypasses the resistor to aid with PSU running efficiency.

Interestingly, PS4 PSU also clicks when you turn the thing on, as did an older Dell XPS 1000W PSU, although that PSU was atrociously inefficient despite the relay! Ugh, the amount of heat that thing belched, it was unimaginable!
 
I said this like 2-3 times already now... :(

My corsair (I said 1150i previously I think but it's probably 1200i yeah) does this little tick with a relay when you start it up. That's the inrush current limiter; it has a resistor in series with the A/C socket and the bigass line filtering caps to let the caps fill up gradually, then the relay bypasses the resistor to aid with PSU running efficiency.

Interestingly, PS4 PSU also clicks when you turn the thing on, as did an older Dell XPS 1000W PSU, although that PSU was atrociously inefficient despite the relay! Ugh, the amount of heat that thing belched, it was unimaginable!


Yes, you did!

I have low inrush beQuiet PowerZone 1000W unit and had no problems at all. Besides us living in 240V world are more resilient for high Watt spikes as usually we have 240Vx15A fuses for sockets :devilish:
 
Sorry Grall, you did say it, but the test for that one was to bypass the UPS which didn't change things. So all I did was combine inrush current with undervoltage protection and a shitty-ass AC wiring job in my old house. I also combined it with the multi-rail lowering inrush rather than a different inrush limiter.

Trust me, you helped me explain things and get all the credit...well, assuming the AX1200i (which you recommended) fixes things ;)

Here's a gold star
Ybeyz00.gif
 
Well, so far GRALL's theory is panning out as the AX1200i fires up the motherboard with no issues. Connecting everything else and starting the idle reboot test will have to wait until later today.
 
Here's a gold star
Aww, thank you, that's the prettiest gold star anyone's ever given me! :D

Now, to see if you actually see a difference in behavior of your system. I'd suggest keeping us posted, but this being a fascinating hardware detective story and all, I'm sure you will anyway.

Crossing my thumbs (or what's the proper expression?) that this works!
 
Fingers is the expression as you cross them on a single hand typically, but thumbs should suffice so long as you don't attempt to operate a motor vehicle with them crossed.
 
Just to keep Grall updated, I went ahead and installed the AX1200i as though it's staying. No idle reboots, but then it hasn't been but a few hours. Here's the thing though...my line conditioner isn't clicking every ten minutes as it used to. Hmm...
 
What's amazing for me Mize, is the fact that you got an UPS that can sustain that 1kW+ PSU of yours.

The UPS must have cost a fortune (assuming it does deliver sine waves output which is likely)..
 

Off topic slightly: that's the exact same UPS that I use on my "big rig" at home. It powers my 1KW Kingwin supply, my Dell U2711 and my cable modem + router + WAP combo. It's fantastic UPS. I have a smaller version of the same UPS powering my home server too.

On topic: Glad you got the PSU figured out, hopefully that resolves the issue :)
 
I use it for my gaming rig (only one of three monitors is connected to it), main switch and my Untangle firewall/router. It's been quite reliable and I recently added a tripplite line conditioner upstream of it...
 
It's the kind of UPS I want, but there's not been any distributors for cyberpower in sweden so it's been unpossible unfortunately... :( Also, last I checked the input voltage wasn't universal, although that probably doesn't matter as a UPS weighing well over ten kilos is hardly the thing you pack when going on an intercontinental trip, so... :LOL:
 
So still no idle reboots but here's the weird part - both HWMonitor and the Asus Probe II software have registered 0 or close to 0 Vcore...but not reboot. LOL.
 
Very very strange. It is sandy CPU you got, yes? Didn't think it supported anywhere near that low vcore. I'm tempted to say it's still a misread (CPU reasonably should crash at zero), even my haswell hasn't gone below 0.032V from what I've seen (which is crazy low as it is). It's gotta be some kind of "microsleep" voltage I'd think where the CPU cores are suspended entirely. Considering sandy is older and with less evolved power saving and has external voltage regulators, I don't know what to think of that low a figure.

However, as long as it doesn't crash, WHO THE HELL CARES! :D So, success, I guess? Or is it too soon to declare victory? How many hours uptime so far?
 
Made it approx 30ish hours before I turned it off. Too soon to declare success, but it's looking that way. I'm off to Montreal for a few days so I won't have the full verdict until the weekend.
 
Made it approx 30ish hours before I turned it off. Too soon to declare success, but it's looking that way. I'm off to Montreal for a few days so I won't have the full verdict until the weekend.

Good to hear!

I hope it works 100% for you and your case is a valuable lesson for everyone living in home with shitty wiring!
To avoid similar problems in future just move to a better wired home instead of changing PSU's :LOL: Less hassle and wife should be happier as well :D
 
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