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Old 04-12-2018, 02:31 PM   #5
AlbanRampon
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Hello,

Very interesting findings indeed!

Our technology is not Graphics Processing Units (GPU), the chips don't compute graphics.
The operating systems will give the desktop composition work to the GPU. When pixels are computed, the OS hands them over to our driver which will encode them, ship them to the dock after USB encapsulation to be hardware decoded in the peripheral.

If I was to make an educated guess, I do not believe the fault is around Windows is here. I would place it on the graphics driver, but I prefer analysis to educated guesses...

There are several possibilities.
- One could be that the platform was *designed* to have performance throttled when the lid is closed. I've seen this in the past because of thermal constraints. You can detect a lid open with on-board display off, but it depends on system conception.
- What is also possible, most likely even, is that the graphics driver decides to go in lower performance mode when there's no direct display connected to save energy because they haven't thought about the notion of indirect displays which became a standard Windows feature in Windows 10 Anniversary Update (so about 2 years ago).
- Another possibility is an OS bug, but unlikely: Windows doesn't decide to shoot down GPU performance on its own. There was a bug around this 2 years ago in the OS, in a similar use case, but with extremely obvious 10-second pauses between updates, and it was fixed within the first month of discovery.

It is a bit more difficult to sense performance changes though, compared to it doesn't work at all.

As a first step to find where this issue lies, I would like to get the machine details from you so this can be assigned to a team to look at.
Would you please use the last link in my forum signature to generate logs and post System_Details.txt? You can remove the machine network name, and username logged in, but I'd really need the all CPU and GPU lines, at least. If you had a description of the application it's most visible on, that would be useful too so we don't spend too much time just reproducing this and focus on analysing it so this can then be routed to the rightful owner.

Kind regards,
Alban
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Alban Rampon
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