USB power stays on in sleep mode :(

My Acer Aspire 4720 has an annoying CPU fan "on/off/on/off" behaviour that is impossible to control via software, so I wired it up with a resistor internally, soldering to a USB +5V header. The fan itself works great, but ...

The USB power (and thus the fan) stays on when I put the laptop into "sleep" mode. In Hibernation, it turns off as normal.

How can I make the USB power turn off when in normal "sleep" mode?

Running OS: Vista Ultimate x64

Thanks guys and gals.

 

Try the following:

Go to the Device Manger > USB Controllers

Select the USB root hubs > Power Managment tab

Make sure Allow to turn off box is ticked on all of them. Try restarting your system to make sure changes are in effect.

 

They were already ticked.

What I'm looking at now is the VGA port for an external monitor (that I never use). It's RIGHT next to the fan, so I wouldn't have to run wiring very far, and it has the optional pin 9 which has a +5V output. Pin 10 is a ground. I already tested it externally with my multimeter and it cut's the power there during sleep.

The question is, does anybody know how much current it can provide? USB I knew could handle up to 500mA. The fan itself normally draws 400mA, after I've added the resistors it's under 200mA. Could the VGA port +5V handle that?

 

VGA isnt designed to take any load. It just has a power rail to detect monitors.

 

I know it's not "designed" for that, but USB isn't designed to power my fan internally either.

0.7V?

http://en.wikipedia.org/wiki/VGA_connector says:

Code:

Pin 9 	SENSE 	+5 V DC from gfx adapter
Pin 10 	GND 	Ground (VSync, DDC)