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Three monitors 20(rotated)/30/30

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jointer
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Three monitors 20(rotated)/30/30

Post by jointer »

Hi,
i have issue with server side of UVNC.
I had 20 inch screen (rotated) and 30 inch, to have the rotated screen properly displayed, i had to install uvnc driver.
All was well until i added another 30 inch, it seems like the driver deactivates when i connect, so i can see all 3 screens, but the left rotated 20" is displayed incorrectly.
The config from left to right: 1200x1600, 2560x1200, 2560x1200.
It seems like the driver is able to work again if i turn off the monitor on right side, but sometimes i need to reboot the machine to get the driver working with the remaining 2 screens.

It seems to me like the driver issue, is there any chance it could be fixed?
The driver is old, but maybe the rotation problem can be fixed in UVNC itself, so i would not need the driver?
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Rudi De Vos
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Re: Three monitors 20(rotated)/30/30

Post by Rudi De Vos »

The driver is indeed limited by the max available kernel memory, if you try to allocate more the the available mem, the driver fail to start. The driver allocate mem for a single rect covering all screens. 6320 x 1600

A full windows 10 multimon review is needed.
It's on the planning..only need to find time.
jointer
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Re: Three monitors 20(rotated)/30/30

Post by jointer »

Thanks,
any chance the original driver could be modified, to allocate more memory and do not crash?
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Rudi De Vos
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Re: Three monitors 20(rotated)/30/30

Post by Rudi De Vos »

A driver require nonpage kernel memory, max is an OS limitation.
Usual you have something like 256MB available for the full OS.

If nonpaged has 0 free or a single block of the required size -> OS stops working
I can remove the limit check in the driver, but a side-effect is that you can lock the OS by activation the driver
jointer
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Re: Three monitors 20(rotated)/30/30

Post by jointer »

This should not be a problem on 64b Win 10 systems any more.
See this info for older systems:
https://blogs.technet.microsoft.com/mar ... aged-pool/
I have 472MB non-paged used and 473MB when i connect with driver active and maximum non-paged limit seems to be around 16GB (the system is dual CPU Xeon workstation with 64GB RAM).
I do not think it is wise to remove the limit completely, but can be probably raised to much higher number (i guess we are talking about megabytes?).
The driver is probably from year 2011 and i am using the "vista64" version without any issues on multiple Win 10 64b systems.
What might be a problem is signing the recompiled driver, i guess it is signed somehow, because i do not need to use Test mode to install it.
I would really appreciate if you could help, it would make my life easier. :)
jointer
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Re: Three monitors 20(rotated)/30/30

Post by jointer »

Rudi, are there any news about this issue?
Thanks
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Rudi De Vos
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Re: Three monitors 20(rotated)/30/30

Post by Rudi De Vos »

Seems the function to allocate the kernel memeory insite a video driver refuse to allocate memory when increased.
"EngAllocateMem()"
Sorry, no solution for now
jointer
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Re: Three monitors 20(rotated)/30/30

Post by jointer »

That is unfortunate.
I am still using it, i just need not to forget to turn the 3rd monitor off before using the VNC.

Thanks for trying to fix it.
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