powering down (not just disabling) a discrete graphics card *at OS level* ? - Overclock.net - An Overclocking Community

Forum Jump: 

powering down (not just disabling) a discrete graphics card *at OS level* ?

Thread Tools
post #1 of 2 (permalink) Old 02-10-2019, 08:04 AM - Thread Starter
Not New to Overclock.net
pulverizor's Avatar
Join Date: Jun 2015
Posts: 231
Rep: 0
powering down (not just disabling) a discrete graphics card *at OS level* ?

ok tis is a tricky one only the best of the best could answer this one :|

so I've a PC with TWO discrete GPU's (and aint got no iGPU)

this is my dual boot setup:

1) OS #1 is windows 10 using the main graphics card (a GTX 1050ti) in the first pcie slot

2) OS #2 is...a legacy windows using a secondary graphics card in the second pcie slot
(long explanation made short: I've had to install that OS recently on a 2nd partition & which I'll have to use on a reguler basis (more often than initially planned) there's no way around this so I'll be stuck with it for a while so that's that)

3) OS #2 CANNOT use GPU1: that GPU's too modern aint no drivers for it hence why I'd to use my spare card for it. I know it sux

> so to sum it up, OS1 uses GPU1, OS2 uses GPU2 (it was hard enough to get OS2 to use GPU2 even after disabling GPU1 in device manager, but I did it)

so both GPU's are connected to my monitor: GPU1 via HDMI, GPU2 via classic VGA

now I noticed OS2 only uses GPU2 after initialization - roughly around login time. in the logon windows GPU2 is used, but till then OS2 uses GPU1 even though I disabled it (I know this cause even if I unplug GPU2 from monitor, I still see OS2 boot up until around login time after which the screen goes black)

and here's the problem: even when booting OS2, GPU1 is still active, from the start, and until reset: which means my monitor receives signal both both GPU2 *and* GPU1 even if I boot into OS2

which means it prioritizes GPU1 even when booting into OS2

which means every time I boot into OS2 I've to manually switch input from HDMI1 to VGA in the monitor settings, to be able to see OS2 logon screen
quite annoying

so disabling GPU1 in BIOS is out of the question (not sure that's possible with my bios anyway it's a Z68 mobo) cause I still mostly use OS1

therefore I need to disable it on OS level, more specifically I need OS2 to automatically power down (not just disable as in device manager) the GPU1 - so that monitor no longer receives input from GPU1 & automatically switches to GPU2 input

how do I do that?

AFAIK there's no way to force windows to "put a component" to sleep like that

(btw in OS2 'sleep mode' is unavailable maybe cause GPU1 drivers cannot be installed)
pulverizor is offline  
Sponsored Links
post #2 of 2 (permalink) Old 02-11-2019, 03:05 PM
New to Overclock.net
Kaltenbrunner's Avatar
Join Date: Dec 2011
Posts: 2,310
Rep: 17 (Unique: 16)
IDK how or what you could do with software to do this.

If both cards used PCIe cables, the easiest hardware hack would be to add a switch(s) on the PCIe cables to turn on/off the power from the each PCIe cable. The cards would still get some power from the mobo tho.

What ever u do, the whole thing sounds like a big hassle, not worth the effort.

Kaltenbrunner is offline  

Quick Reply

Register Now

In order to be able to post messages on the Overclock.net - An Overclocking Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Forum Jump: 

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off