can i use a 12v from my PSU while the PC is off?

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chronic9

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thinking of modding a rasPI and a 3.5 hdd into the bottom of my case to use as a 24.7 download appliance.

Is it possible to use a 12v line without turning on the entire PC? I was thinking that its not possible, since the 24 pin is plugged into the motherboard. In the past ive used the paper clip trick, but that wouldnt work this time around would it?
 
I am the opposite of an expert here, and certainly wouldn't try on my gear, but here is what I think.

1) No it won't work without some sort of bypass
2) You could force it to work by using the "paperclip" trick..basically you could splice into the same wires you would by throwing the paperclip in there and add a switch. This would allow you to "paperclip" and power the raspi
3) When "paperclipping" I am thinking you will also power on anything plugged into the PSU...aka your HDD for your main rig, etc.
4) No idea what this will do to your motherboard

Minimal help I know...but I am bored. Hopefully someone smarter than me answers.
 
how much does the usb3.0 quickpower slots provide, because they are always on sockets. if they provide the12v, then you could just wire into them. Saying you have the quickcharge 3.0 usb that is. look into it :)
My only help to ya :(
 
ya i saw that option in BIOS last night, so my board supports it.
anyone know how much voltage it provides?
 
y0bailey said:
I am the opposite of an expert here, and certainly wouldn't try on my gear, but here is what I think.

1) No it won't work without some sort of bypass
2) You could force it to work by using the "paperclip" trick..basically you could splice into the same wires you would by throwing the paperclip in there and add a switch. This would allow you to "paperclip" and power the raspi
3) When "paperclipping" I am thinking you will also power on anything plugged into the PSU...aka your HDD for your main rig, etc.
4) No idea what this will do to your motherboard

Minimal help I know...but I am bored. Hopefully someone smarter than me answers.
Click to expand...

ya, thats essentially my thought process as well on this.
 
USB only provides 5v, so no, thats not gonna work.

Paperclipping the PSU while hooked up to the mobo will at best turn on the whole machine, at worst burn shit up.

Get a power brick, and save yourself trouble.
 
The main 12V is a PCs power source, it cannot be on while the PC is off.
But there are some implementations of USB power that can do what you want.
ie the spec exists for 12V via USB.
Whether PSU mfrs implement it is another matter.

http://en.wikipedia.org/wiki/PoweredUSB
 
i wonder if i can daisy chain a rasPI and a 2.5" enclosure off a single usb3 port

USB3 port ===> RasPI:usb port ====> 2.5" usb enclosure
 
chronic9 said:
i wonder if i can daisy chain a rasPI and a 2.5" enclosure off a single usb3 port

USB3 port ===> RasPI:usb port ====> 2.5" usb enclosure
Click to expand...

RPi documentation warns against operating it off of a computer's USB power supply because of (supposed) current inconsistencies. On the other hand, it's not like RPi's are particularly expensive, in case it does in fact get damaged. But wall-wart USB chargers are like a dime-a-dozen. If you want a clean look, just pipe in an external usb power cable from a sufficient wall-wart into the computer chassis (not like there aren't already cables going to-from a regular computer case in the first place), and plug it into the RPi's micro-USB port in its cozy little resting spot. My $0.02.
 
Thanks for that bit of knowledge.
I am using a 5w apple brick on my RPi right now, maybe step it up to a 10w and hopefully it can power a 2.5 drive as well.
 
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