• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

My Q950 PSU died today!?

ktkm

Well-known member
A weekend of power supply madness that I thought would end after successfully re-capped my IIsi PSU on Sunday turned for the worse when I noticed my Q950 wouldn’t start anymore. I feel cursed, or at least that the IIsi sucked the life out of the Q950.

@BadGoldEagle , how is the project coming along?
 

joshc

Well-known member
I feel your pain, I've had to deal with lots of dead power supplies.

You may want to consider an ATX replacement like this one:


Pretty easy to do, doesn't require custom PCBs. You just have to find a good enough PSU with a strong 5V rail.
 

BadGoldEagle

Well-known member
@ktkm What are the exact symptoms? What's happening with the key in the lock position? Does the relay even click? Did it trip your breaker?
I only know of two failure modes: AC short to ground (almost caused a fire and killed my floppy drive) and 5V resets.

As a temporary solution I'd build the custom harness (even easier than gutting the power supply) we talked about some months ago.
You can buy any ATX extension cable to do this. With some staples you can remove the contacts from the connector housing and easily rewire everything.

As far as the QuadrATX Project goes, I'm still looking for a solution for the power switch. I was forced to take some time off for the Christmas Holidays, so I'm hoping to finish everything by January 8.
 

ktkm

Well-known member
You may want to consider an ATX replacement like this one:
Thank you for the tip! That is the plan, @BadGoldEagle helped me out a while back finding a candidate with a good 5 V rail (and lots of other stuff).
You don’t have the key/ power on circuitry turned off, do you?
I checked every detail, key, power cord, keyboard, and video, and I even unplugged the KVM shared with an IIfx.
What are the exact symptoms?
The symptoms were plain silence … but after switching the outlet strip off and on a second time a couple of hours later, the Quadra suddenly came back to life. I don’t know what to make of all this. The Quadra and IIfx share the same outlet strip, and the IIfx booted just fine when this ordeal started.
 

ktkm

Well-known member
Here’s my set-up at the moment, could it be too much stuff hooked up to one outlet strip?

IIfx_quadra950-setup.jpg
 

LaPorta

Well-known member
Not that I am an electrical engineer, but I would suspect you'd trip either the power strip breaker (if so equipped) or the actual circuit breaker before there was an issue with unrestrained current overdraw. That looks fairly typical for what I run with no issue at home. By the way, I like the ecclectic setup.
 

Cory5412

Daring Pioneer of the Future
Staff member
That's a great looking setup, love that it's sit/stand too -- do you find the IIfx and the ACHRRGB display are too heavy/do the motors get angry at you?

As far as I know, most power strips are designed to trip before an average ~110v/15a circuit itself will. If you trip the circuit at the panel in your home but not the power strip, it's probably time to replace the power strip or get one more appropriately rated to whatever your circuit and in-wall wiring can handle.

If the cabling from the power strip to the wall isn't hot then I'd say you're not overloading it. (You can also turn everything off and insert a power meter like a kill-a-watt to measure.
 

cheesestraws

Well-known member
Yeah, that's a very classy setup (though suspiciously tidy ;-) ).

That doesn't look unreasonable for an extension lead to me?
 

ktkm

Well-known member
That looks fairly typical for what I run with no issue at home. By the way, I like the ecclectic setup.
Thank you!
That's a great looking setup, love that it's sit/stand too -- do you find the IIfx and the ACHRRGB display are too heavy/do the motors get angry at you?

As far as I know, most power strips are designed to trip before an average ~110v/15a circuit itself will. If you trip the circuit at the panel in your home but not the power strip, it's probably time to replace the power strip or get one more appropriately rated to whatever your circuit and in-wall wiring can handle.

If the cabling from the power strip to the wall isn't hot then I'd say you're not overloading it. (You can also turn everything off and insert a power meter like a kill-a-watt to measure.
Thanks! The monitor stand helps keep even pressure on the IIfx. However, some days it seems as if the ACHRGB (I love the acronym btw. -- T-shirt material!) is very picky about ESD and turns itself off due to X-ray protection, I was told? Even worse so if I wear Birkenstock sandals that are not ESD protected.
 

joshc

Well-known member
@ktkm I can't stop looking at your setup photo, it just looks so nice! I have most of the stuff there but none of it is set up nicely like that. This is really inspiring, I especially like the fact your Q950 is on a stand with wheels... :cool:
 

BadGoldEagle

Well-known member
@ktkm Great to hear it's back up and running. I guess the PSU's safety "switch" could have kicked in for a bit, or the caps are weak...
Again, I know this really sounds like an old tune but how do you plug it in? Do you have a switched outlet?

Also, where did you get that stand? The one I got last year on amazon is slightly too large.
 

ktkm

Well-known member
@joshc Thank you! The setup results from inspiration from this site and many hours spent trying to figure out what I need. :)

@BadGoldEagle I use a switched outlet strip, and thanks to you, I always switch it off before I plug in the Quadra. The stand I bought a year ago from a Swedish cart and weel shop in Stockholm called Tellus <https://www.tellus.se>, and they had a stand that just happened to have the same footprint as the Q950.
 
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