CMOS battery

Ardy

Member
Hello everyone. Is it normal for my CMOS battery to be powering the GPU and USB External HDD?
When I unplug the machine. The GPU light is still on and the Ext. HDD light is still on.

Thanks

Ardy.
 

porterjw

Spaminator
Staff member
As in physically unplug the system from either the wall outlet or the PSU?

Is it possible to keep the indicator lights on? Yes. Is it possible for it to power the components? Not even remotely. Power will still remain in the capacitors for a short while, though it's simply a residual charge and nothing that can be used to start a component, let alone keep it active. Also, the lights you see are just showing that there is a connection to the system - your ethernet port (most likely) does the same thing. With the system physically unplugged, press the power button - chances are you'll see a quick flicker of light or turn of a fan as the remaining power in the capacitors is fully discharged. If your GPU and ExtHDD light are still lit, it's drawing from the CMOS battery; an issue if left unplugged since even a small power draw will deplete the battery after a while. However, if left plugged in and the lights are on even when the system, is off, it's normal.
 

Ardy

Member
Yea when I completely unplugged the system from the wall the lights were still on. What can I do?
 

porterjw

Spaminator
Staff member
Press the power button to discharge the capacitors.

If the lights go out, there's nothing to worry about. If they stay lit, they (the indicator lights, not the components themselves) are drawing power from the CMOS battery and should be unplugged from the system to prevent premature drain.
 

Ardy

Member
Hi porterjw. Thanks for your help
Do you mean push the power button for just one second or hold it until the light goes out?

Thanks for your help

Ardy
 

porterjw

Spaminator
Staff member
With the system unplugged, just push the power button - it's pretty much instant. The amount of residual juice left in the capacitors is only enough to power the system for well under 1/4 second..
 

Ardy

Member
Hi I unplugged the PC from the wall and then pushed the power button. But it still didn't turn off. Should I leave it and see what happens or could it drain the CMOS battery? What happens if the CMOS battery dies?

Thanks for your help

Ardy
 

MyCattMaxx

Active Member
The CMOS battery isn't even tied into the GPU or USB jacks.
You need to look elsewhere.

Edit: You haven't even told us what your system is.
 

Ardy

Member
Ok Sorry I have a:
ASUS GTX 970
i7 4790K at 4.6 GHZ
Z-97-A ASUS Motherboard

Do you think it could just be the Capacitors taking a really long time to empty out?
Should I leave it and see what happens?

And I am completely sure that the PC isn't connected to the wall.

Ardy
 

johnb35

Administrator
Staff member
Look in your program list for a program called Asus Ai Charger and uninstall it. This program allows current to flow to usb's to allow charging of cell phones and media devices.

The cmos battery has nothing to do with the issue at hand. The cmos battery only keeps the bios settings in tact while the machine is off and thats it.
 

Okedokey

Well-Known Member
You're detecting residual capacitance. Mine takes over 30 seconds to discharge after disconnection.
 

Ardy

Member
Ok I didn't find anything called Asus Ai Charger and I will just leave it unplugged and see what happens.

Thanks
 

Ardy

Member
Hi there guys. I found the problem. I have a Saitek pro flight yoke that is connected to external power which is then connected via USB to my PC.

Thanks for your help. I appreciate it a lot.

Ardy
 
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