Odd NF7-S behavior

I noticed something odd last night when I popped my new NF7-S into my system. My matrix orbital LCD display lit up when I pugged my power cord in. I don't ever recall that happening on my old system and couldn't wait fire up the system. I have just shut it down and there it goes again still lit up.

Now that I have sat to think about it I figured out that the lcd display is pulling power from the USB port. I unplug the usb cord and sure enough the display goes off. Is this normal? I don't recall ever having a usb device draw power from a pc that was turned off before! Perhaps I just never noticed this before. Really my old rig was on almost 100% of the time but I gotta think this never happened. I mean I noticed it the INSTANT I plugged in my machine.

The USB's should have power to them at all times while the ATX PSU is plugged in...the ATX PSU's have power flowing through them even when turned off...this is why you MUST unplug the PSU cord and "discharge" the power in the ATX PSU before working on a ATX system....when I say discharge...I mean...unplug the cord and then just hit the power button...this is not a full discharge but enough to where you wont short anything out when working on the system...

USB pulls power off the +5VSB line. This is required so a USB device can bring the computer out of standby.

kct2 said:

USB pulls power off the +5VSB line. This is required so a USB device can bring the computer out of standby.

Click to expand...

Ok this makes sense. I obviously realize that you need to discharge power from the pc when working on it. I hadn't considered the reason why the usb ports are given power, even when the machine is powered off. I wonder if my lcd got into some weird state where it does not shut off or something. Any other usb device would not pull power with the pc shut off (for example an optical mouse does not stay lit up with the pc off).