More on my LCD powersupply issues.

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Jon's picture
Jon
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So, back a while ago:
http://www.applefritter.com/node/4540
http://www.applefritter.com/node/4797
http://www.applefritter.com/node/4704

All having posts relating to a GVision LCD I have. My next go around is about this thing which seems like it would put a load on the 5v line of a power supply, just like I need. The GVision is powered by the 12v line, and some comments lead me to think that having some draw on the 5v would be a good thing. If I plugged this and the GVision in to an otherwise bare powersupply (AT or ATX) would it be all right by itself? I'm wanting to use a cheap low wattage p/s to drive the GVIsion w/o needing to run off a particular machine's p/s ie. if/when I get my mini and/or get a KVM setup going.

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The Czar's picture
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I would imagine that it would

I would imagine that it would work, but a simpler (if not more elegant) solution would be to plug in a standard PC case fan. That should put enough load on the PSU to keep it running.

However, if you're using an ATX powersupply, you can short the green wire to any black wire (ground). For more information, you can check out here.

Cheers,

The Czar

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Jon's picture
Jon
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It's not the turning on that

It's not the turning on that is a problem, but having a balanced load on the 5v and 12v lines, I guess. When I tried an AT supply and just the 12v line, it didn't give enough voltage to run the backlight on the LCD.

Thanks for the fan idea, it might be a good idea as the LCD has two CCFL tubes that do generate a bit of heat.

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The Czar's picture
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That's peculiar indeed. 12v i

That's peculiar indeed. 12v is supposed to be 12v, no ifs, ands or buts about it.

What's the amperage on the lines in question? Depending on the PSU, it may not be able to pump out enough juice to power the backlight. The specs quoted on many PSU's are the maximum power available over a short amount of time, ie: burst power when a device is starting up. Most PSU's can only sustain between 75-80% of their burst capacities over the long run. That would mean you'd need at least 6.25A burst capacity to power a 5A device for any amount of time.

Cheers,

The Czar

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Jon
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The same p/s hooked to a mobo

The same p/s hooked to a mobo and the LCD makes it work fine. That's how it is working ATM. I'd like to get it to work on a p/s by itself so I don't need to have it tied to a particular machine. I can get a high amp 12v supply for about $100-200, but I'd much rather use a free-$5 AT/ATX supply for obvious reasons. Smile

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