CRTEmudriver + Windows 10 - squeezed picture on first boot?

[Dexje]

Hi,
i´m running CRT Emudriver & CRT Tools 2.0 beta 12 on Windows 10 1709 with an AMD R5 230 flashed with ATOM15 to 31khz in an Naomi Universal cabinet (so a 31khz screen).
If i boot up the pc for the first time the image is vertically squeezed. If i reboot the pc everything is perfect.

How can i fix this?
I think i have read about this somewhere already .. but cant find it again 

[Dexje]

can nobody help?
this is what it looks like (in windows and mame - the bootsequence is fullscreen):

after one or two reboots everything inside windows is fullscreen aswell...

[buttersoft]

can nobody help?

We're thinking, we're thinking:)

Do you have other sources or monitors to test things with? If that's a 31kHz-capable screen for the Naomi, you could just plug it straight into an LCD...?

If i had to guess right now, it sounds more like it's going to be something to do with the dual- or tri-sync circuit on the chassis. Like, you're booting into a super resolution and the high pixel clock at 15kHz is pushing the vertical deflection a 31kHz size range. I'd google for that and see what comes up. Or maybe post in the monitor and video subforum on here if you can't dig anything else up. This is just a guess though.

[Calamity]

Hi Dexje,

The issue you're seeing is due to the video card not being properly reset on wake-up. When you shut Windows 10 (and 8, 8.1), it actually goes to sleep instead of really turning off as it did in Windows 7. This makes the subsequent boot process faster, but probably drivers are loaded directly on ram from a disk image, bypassing their startup sequence.

CRT Emudriver relies on a hook in its startup sequence to clear some stuff that ATOM-15 turns on during boot in order to output interlaced modes properly. When this is bypassed, you get that issue. If you restart your system manually, Windows goes through the full boot process instead, which leads to proper driver initialization.

A possible fix is to force Windows 10 to always shut the system completely instead of going to sleep. I don't know if this is possible these days, probably it is.

Another fix, even if it's an ugly one, is to force a reset of the video card device on Windows startup. Check this post.

Finally, you may get rid of the issue by avoiding the use of interlaced modes on boot. Since you have a 31 kHz monitor, the interlace mode you must be seeing is 1024x768i for the Windows logo. Try to change the Windows startup options to use "base video" (640x480) instead. This will disable the fancy logo and set a Vista-like one. I don't now if this is even possible on 10, it was on 7.

[buttersoft]

Interesting, i didn't know any of that.

About shutting down, it seems you can disable fast boot for windows. Power Options > Choose What The Power Buttons Do (on the left side menu) > Change Settings That Are Currently Unavailable > uncheck fast boot. I wonder if this will fix it. It's supposed to turn off loading the state windows was in, preventing the hibernation-like shutdown.

[Dexje]

@buttersoft: your setting worked! 

@calamity: the devutil64 reset did nothing in my case, but buttersofts suggestion worked. thank you for all the work you do!

[buttersoft]

Hah, Calamity deserves the credit. All i did was hit up google after he nailed down the problem