What's new
By:

Consolized Naomi won't power off. Micro ATX issues...

nam9

nam9

Champion
Joined
Aug 24, 2015
Messages
1,348
Reaction score
1,359
Location
Norway
Hi,

I am using a micro ATX PSU to power my Naomi 1 board.
I have connected PS-On to a simple 1 pole switch. Switching to the 'On' position shorts PS-One to Gnd and the Naomi powers up.
Switching to the 'Off' position... The Naomi stays switched on...

The motherboard is connected to the 24pin power block.
There is an additional 4pin block (12v, Gnd, 5V, Gnd) that i am using for the main system fan.
The fan powers on and off as normal...

Am missing something simple here...?
 
You need to leave the PS-On shorted permanently and instead wire an on/off switch to the power cable input itself.
 
Not sure a momentary switch would work...

As i mentioned - I tested the setup before adding the motherboard.
Switch on -> power and case fan running. Switch off -> no power, no fan.
(NB, case fan now wired to PSU, not through motherboard).
Now with motherboard attached:
Switch on -> as expected. Switch off -> case fan stops, motherboard still running...

A momentary switch would power up the motherboard, but not the case fan...
I would need to test whether holding a momentary switch would result in motherboard power off...

I'll post up a picture later.
 
Normally, an ATX supply powers on when the green wire is connected to GND. If you disconnect it, it should power off again.

Some voltage rails keep delivering power like the 5V SB (stand by) Those are used in a pc for features like "power on lan"
Some keyboards have a key that can power the system as well. Some mobo's have usb ports that keep delivering power, even when the pc is turned off.

My guess is that your Naomi somehow is still powered by that standby voltage. If the supply would stay on, the blower should stay running as well.

So indeed, disconnecting the mains will power it down completely.
 
Of course a switch on the mains line would work.

What PSU are using? Do you have link to it or datasheet.
 
Need to see the whole thing and a link to wherever you bought this or a datasheet. I see one end of the PSU, that just looks like a dc-to-dc converter, you should have at least a ac to dc adapter, probably something in the range of 19-24v at around 8-10amps.
 
Hey. Here is a pic of my setup:

20170131_212053.jpg


You can't really get a good look at the ATX PSU as it is mounted vertically. It is the one pictured in the first link. It is a DC-ATX adapter.
It takes a 19V 11.5A laptop PSU to power it. Its by a company called HDPlex who are worth a look.
Unfortunately they have just replaced this model with a new form factor that looks more like the PicoPSUs.
The old spec pages are now gone for this model, but it is pretty similar to the replacement (here).
The green wire with the black heatshrink is the PS-On connection that is attached to the power switch, top left.
The white board is the barrel plug for the laptop power supply.

Cheers.
 

Attachments

  • 20170131_212140.jpg
    20170131_212140.jpg
    251.7 KB · Views: 124
Well, the quick & sure thing to do if to leave the PS-ON connection jumpered and connect the switch to the the DC barrel plug to interrupt power from getting to the DC-ATX board. Like its been said, the PSU could still be supplying power although its been turned off. You could always ask the company for a replacement psu; at the very least ask them to verify if it still supplies power when turned off.
 
Last edited:
Yep. I've emailed them and their rep said he'd ask an engineer to clarify.
 
I assume the supply came with it's own cable to connect it to a pc motherboard.

You basically bypassed that cable or simply used one of it's connectors.

Are you sure they didn't switch some pin's in that cable.
I mean, did you double check that all the supply connections are what they are suposed to be?
It's hard to see on the foto's. And even if it would be visible, we don't know if that supply connector is wired as a normal ATX power connector.

Maybe, you can measure what voltages remain if you switch the unit off. Is it only the 5V or is only the 12V turned off?

It could be a bad supply or it could be connected wrong.

They likely didn't use a separate step down for the 5VSB voltage and simply use the 5V step down for 5V and 5VSB. If the 5V isn't disconnected properly, you might get your behavour.

That's why it's important to know if the 3V3 stays on or not.
 
Hi. The supply came with its own male to female atx adapter (which i have chopped for my install). It was a straight through 1:1 cable.
I have checked that i have not connected the 5VSB pin to anything (I haven't) but you make a good point. I'll check what is still active.
 
obcd said:
My guess is that your Naomi somehow is still powered by that standby voltage. If the supply would stay on, the blower should stay running as well.

So indeed, disconnecting the mains will power it down completely.
Click to expand...
This ^

The Naomi is drawing some standby voltage from the ATX PSU and not shutting down.
Measure all three (12v, 5v, 3.3v) voltage lines going into the Naomi with the PSU off but the Naomi still on...
I suspect you will find 5v is still very much active. ;)
 
Yup, probably still active on the 5V.

I say just wire the switch to the 19v line coming from the laptop psu.
 
So. Motherboard fitted -> powered on.
Power off -> 1v on 12v line, 5v on 5v line and 3.3v on 3.3v line...
 
That sounds like a defective supply. 5V and 3V3 should switch off as well.
Only 5VSB should remain at 5V
 
obcd said:
That sounds like a defective supply. 5V and 3V3 should switch off as well.
Only 5VSB should remain at 5V
Click to expand...
Totally agree, have these replace it, must be the part of the reason they changed their design.
 
You must log in or register to reply here.
Back
Top