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Software Support => GroovyMAME => Topic started by: siastbill1 on October 02, 2018, 11:51:11 pm

Title: Quick Atom-15 Question
Post by: siastbill1 on October 02, 2018, 11:51:11 pm
Hello,

Atom-15 has been working great for me in terms of the text display during POST as well as inside the bios config utility. When Windows 10 shows the Windows boot logo, I lose sync and the screen is a distorted mess. Then when windows loads, the CRT-Emu drivers make everything good again. I'm using the MSI Radeon 6450 hooked to an Electrohome G07.

I just wanted to confirm that Atom-15 will completely suppress any 31khz and up modes, such that even though my monitor is having trouble syncing during the Windows boot logo, its not actually going to be doing any harm. (Not sure what Vesa mode Windows 10 uses for the boot logo).

Thank you!
Title: Re: Quick Atom-15 Question
Post by: buttersoft on October 03, 2018, 12:38:19 am
It's not Atom15 doing it, Atom15 is great once installed. It's an issue with Win10.

It's only for a second or two, and i'm not sure how out of spec it is - sometimes i find it does sync, but then sometimes not. I have a PVM-2730 i can test with, as those will sync to a really wide range around 15kHz - though i'm not saying it's healthy to keep pushing that either. And I have noticed the behaviour change as Windows updates itself.
Title: Re: Quick Atom-15 Question
Post by: Zebidee on October 03, 2018, 04:58:49 am
You can change the Windows boot logo image to something else, custom image of your own, or even just a black screen if you want to bypass showing anything at all because of sync issues. It's covered in the Hiding Windows tutorials that are pinned somewhere, Software forum I think.
Title: Re: Quick Atom-15 Question
Post by: alex2005 on October 03, 2018, 06:35:15 am
How does windows 10 work like at 640x480 15khz?
I recall it had some weird resolution (probably aspect ratio was not really user friendly), which made it difficult to navigate and in general, use it.
Has this been improved somehow on the latest windows builds?
Title: Re: Quick Atom-15 Question
Post by: siastbill1 on October 03, 2018, 07:27:27 pm
Hello,

I actually used bcdedit to disable the Windows 10 bootux. https://docs.microsoft.com/en-us/windows-hardware/customize/enterprise/unbranded-boot

Odd thing is even with it now displaying a black screen, I still see a few white anomalies flickering here and there. This makes me think it is still using the same video mode, and just drawing black pixels. You mentioned it was a Windows problem. Is this because Windows 10 isn't using a Vga or Vesa video mode for the boot logo, but rather something more akin to a driver (just not crt-emu). It lasts the entire duration that the boot logo is on screen though, so sometimes this is more like 10 seconds.

In regards to the question about win 10 and 640x480. Im finding I can do most Windows stuff fine, but many apps expect a larger resolution and they get cutoff and are unavigatable.

Thanks!
Title: Re: Quick Atom-15 Question
Post by: krick on October 03, 2018, 09:41:58 pm
Odd thing is even with it now displaying a black screen, I still see a few white anomalies flickering here and there.

On Windows 7, when I disable the Windows boot logo, and boot with a normal LCD monitor it shows a blinking white cursor in the upper left corner briefly.  That's probably what you're seeing except it's out of sync on the arcade monitor.

My understanding is that ATOM-15 limits the card output to 15KHz but only while the card's BIOS is in control.  As soon as Windows takes over (during the display of the logo or the black screen in your case), then ATOM-15 is out of the picture.

As buttersoft pointed out, it's probably Windows being out of sync briefly when switching from the logo mode to the desktop mode.

I'm not really sure how we could fix this issue.  I don't think there's any way to change the video mode Windows uses at that point.
Title: Re: Quick Atom-15 Question
Post by: siastbill1 on October 03, 2018, 10:51:47 pm
Thanks Krick. It's definitely not the brief issue between switching from logo mode to windows mode. It is literally out of sync the entire time the boot logo is being displayed (like 10 seconds). This is from the moment Windows starts to boot until I see the welcome screen.

This older post from Calamity indicates that Windows XP used bios mode 12h to display the boot logo. That means that Atom-15 would have covered that use case. For Windows 10 (and probably Windows 7+ really), do we know for sure that Windows is not using the VGA or VESA bios of the video card to display the boot logo?
http://forum.arcadecontrols.com/index.php/topic,142267.msg1473596.html#msg1473596 (http://forum.arcadecontrols.com/index.php/topic,142267.msg1473596.html#msg1473596)

 
Title: Re: Quick Atom-15 Question
Post by: krick on October 03, 2018, 11:40:46 pm
The issue doesn't affect me as much because I run everything through a JPAC (since early 2004!!) which halves the 31KHz signal and displays it as a split-screen 15KHz signal.  Once I changed my motherboard bios splash screen to show a completely black screen and the Windows boot logo to the black screen, it's a barely noticeable blip on the way to the Windows desktop.

However, there is some small text at the bottom of the motherboard BIOS screen.  On my previous motherboard, I used (AMI) BIOS editing tools to remove the text strings too.  I haven't done the legwork to see if those sort of tools exist for my current motherboard BIOS and I'm not sure if the reward outweighs effort and risk.

Additionally, my current motherboard uses a UEFI BIOS so if I actually need to enter the BIOS and make changes I have to remove ATOM-15 and connect the PC to a normal PC monitor anyway.  So in that respect ATOM-15 becomes more of a pain than it's worth.  It's easier for me to just not use ATOM-15 at all and let the JPAC split everything (after making it all black).
Title: Re: Quick Atom-15 Question
Post by: buttersoft on October 04, 2018, 02:26:11 am
The issue doesn't affect me as much because I run everything through a JPAC... which halves the 31KHz signal and displays it as a split-screen 15KHz signal.

dude, a split-screen 15kHz signal is 31kHz!  If you mean side-by-side images it is, anyway.
Title: Re: Quick Atom-15 Question
Post by: Calamity on October 04, 2018, 10:10:49 am
dude, a split-screen 15kHz signal is 31kHz!  If you mean side-by-side images it is, anyway.

When a 31 kHz signal passes through the JPAC, it will filter out every other H sync pulse, resulting in a split screen which is actually 15 kHz.
Title: Re: Quick Atom-15 Question
Post by: buttersoft on October 04, 2018, 11:38:47 pm
dude, a split-screen 15kHz signal is 31kHz!  If you mean side-by-side images it is, anyway.

When a 31 kHz signal passes through the JPAC, it will filter out every other H sync pulse, resulting in a split screen which is actually 15 kHz.

Oooh, i never knew that, that's pretty cool. Thanks. I figured the j-pac just locked out anything that wasn't 15kHz. Can it filter any other frequencies, or only 31kHz?