Trying to stop my PC powering my HDMI/USB switcher when turned off (cmos question also)

Scam · 1 Dec 2020 at 16:52

I have my work's Macbook Pro and my Win10 PC plugged into a cheap HDMI/USB switcher to enable me to use the same keyboard and mouse when switching between them. Works great.

However the switcher insists on staying on and showing a bright blue light when (a) my Macbook is plugged into it via the usb-c dongle and (b) when my PC is turned off.

I'm getting nowhere with the Macbook, it seems Apple are perfectly happy to let devices draw power from usb-c even when it's asleep, even when it's not plugged in itself :confused:

But that's fine I can unplug the dongle...

But now that I need to keep my plug extension for my PC gear on (due to using a powerline adapter), it seems the switcher is staying on as it's getting power 'through' my PC.

I've google and found these steps for Win10;

1 - Go to Control Panel > Power Options > Change Settings Scheme > Change Advanced Power Settings > USB Settings > and deactivate Selective Suspension;

2 - Go to Control Panel > Power Options > Choose What Power Buttons Do > Activate Settings Currentlly Unavailable > scroll down to Shutdown Settings > disable Activate Fast Start.

But they've done nothing.

Seems I might want to check in my BIOS ERP settings, but I have fast-boot enabled so that is proving difficult. Sounds like I need to clear my cmos to get into my BIOS, but I'm wondering what other settings I might lose by doing that? :confused:

It's not a complex build, just one boot SSD, one media HDD...

Thanks for any ideas.

mickyflinn · 1 Dec 2020 at 17:00

Hold down the F2 key, then power on your pc you should be able to get into the bios.

alec · 1 Dec 2020 at 17:00

for the fast boot issue
create a shortcut with command
"C:\Windows\System32\shutdown.exe /r /fw /t 0"
This will reboot computer straight into bios.

Scam · 1 Dec 2020 at 17:40

alec said:
for the fast boot issue
create a shortcut with command
"C:\Windows\System32\shutdown.exe /r /fw /t 0"
This will reboot computer straight into bios.

That's brilliant thank you. At least I can check the ERP settings without clearing my BIOS/CSMOS. Will report back...

mickyflinn said:
Hold down the F2 key, then power on your pc you should be able to get into the bios.

Yep wasn't working because of fast boot (and I think it's DEL for my mobo)

Scam · 1 Dec 2020 at 18:48

alec said:
for the fast boot issue
create a shortcut with command
"C:\Windows\System32\shutdown.exe /r /fw /t 0"
This will reboot computer straight into bios.

Hmn it does not work. When trying to run it from cmd I get this;

A required privilege is not held by the client

t31os · 1 Dec 2020 at 19:10

Try from an elevated(run as admin) command prompt.

Scam · 2 Dec 2020 at 11:28

t31os said:
Try from an elevated(run as admin) command prompt.

No dice. Seems to be related to Local Policies / User Rights but I can't find a fix for Win10. Everything seems to be talking about WinXP..

EDIT: Tried this but slightly confused what to do.. http://techgenix.com/cantshutdownfromcommandline/

t31os · 2 Dec 2020 at 13:19

Any error message? What happens?

I'd be inclined to just take out the motherboard battery for a 10 - 20 secs, you'll lose your bios setup but you're almost certainly be prompted to enter the bios and reconfigure when you start up again.

Many modern boards provide a load and save profile option in the bios, after you get everything configured, save it as a profile, so if you ever need to clear the bios again you'll have a nice and easy way to restore all the settings.

Scam · 2 Dec 2020 at 13:46

t31os said:
Any error message? What happens?

I just get the same user privilege error when I try to run the command from cmd prompt. The shortcut just doesn't do anything. I'm inclined to agree with you re. resetting the cmos (my mobo does have jumpers). What settings might I lose besides time and date etc? Boot order, things like that? My setup isn't overclocked or anything, I only have my OS ssd and media hdd so nothing complicated. What else would I need to check in the bios once I've cleared the cmos?

t31os · 2 Dec 2020 at 13:59

Date and time, and boot order (if it doesn't default the right order), i'd expect most things to auto-config reasonably well (depends on the hardware). You might want to turn off onboard features you don't need, set fan settings, temp warnings etc... you'll just have to go through and tweak as you feel is needed (if you don't understand what a setting is or does, leave it be).