Groovy Arcade bad default resolution

[mamenewb100]

So I wanted to try out Groovy Arcade with a CRT I had laying around. I made a bootable DVD of GA and I have an LCD for my main monitor. After booting into the CD I select a 15Khz option and the installation continues on my CRT. The problem is that GA picks a resolution that is way too high like 800×600 and I can't read the text on the TV.

I have tried editing the startup line by pressing tab and manually entering a lower resolution. A menu even pops up telling you to pick a Resolution but no matter which one I choose it always defaults to the same unreadable resolution like its being ignored. Is there a way to install a 31khz version of groovy arcade and then use 15KHz later?

[Substring]

Hi,

I don't get you : you select 15kHz but you get 800x600 ? Hardly any chance this happens. There is a strange linux behaviour with 31kHz where linux doesn't work the expected way and sets a default 1024x768. You have several ways to fix that :
- be patient and wait for the march iso release
- manually edit kernel options and force a specific edid

Still I don't get why you'd go 31kHz to then set 15kHz ...

Regarding the boot resolutions : there are just a few ones available, i didn't add a full switchres inside the kernel.

But what is sure : 15kHz sets 640x480i. If you boot with multiple monitors plugged, the resolution is added to each video card connector, meaning a recent lcd won't use it and rather display at its native resolution

[mamenewb100]

Hi,

I don't get you : you select 15kHz but you get 800x600 ? Hardly any chance this happens. There is a strange linux behaviour with 31kHz where linux doesn't work the expected way and sets a default 1024x768. You have several ways to fix that :
- be patient and wait for the march iso release
- manually edit kernel options and force a specific edid

Still I don't get why you'd go 31kHz to then set 15kHz ...

Let me explain... I have a couple of issues. First I have a modern Nvidia video card as my main LCD display hooked up through Displayport. And also running HDMI through a HDMI TO VGA Adapter so I can connect my TV with composite. I also have an old ATI 4550 that my BIOS refuses to display through HDMI but is detected fine in Windows. It may work with an analog VGA adapter but I haven't received it yet. So I am just trying to install through my main video card for now and switch to a more compatible card that can display true 15Khz resolutions later. Unless this isn't possible?

 

But what is sure : 15kHz sets 640x480i. If you boot with multiple monitors plugged, the resolution is added to each video card connector, meaning a recent lcd won't use it and rather display at its native resolution

When I first boot Groovy Linux from the 2020 Live CD it only displays on my LCD. Only AFTER I select one of the options for 15Hz does it switch to display to the TV and the LCD is out of range as expected. The reason I wondered if could keep 31Khz for installation is because the image displayed on my TV is way to small to read. You are probably correct that it is displaying 640x480i, it just seems larger because the text is all smooshed together on a low resolution display. The images tell the story. I've also tried to edit the display options by pressing Tab and it even gave me a choice of many resolutions. However, it always defaults to the same resolution.

So I am not being impatient or bashing on developers. Sorry if it came across that way. Just trying to figure out how to display a more readable resolution. It's probably just my odd setup. I'm currently waiting on an analog VGA adapter as I think I'm complicating the issue with a Digital-to-Analog conversion and may be part of the issue.

[Substring]

OK now I have a better picture of it :

When the PC boots, until it reaches the syslinux menu (where you choose 15/25/31 etc ...) : that's the good old BIOS resolution (640x480 at minimum) unless you have a AMD GFX card flashed with atom15. So, until you select one of the horizontal frequencies, you're at 31kHz. No difference with Windows here.

Once you've selected which mod to boot, the linux kernel loads and sets the desired resolution. From now on, you're supposed to be on 15kHz.

Now, a little more details, as I've tried with multiple monitors too just now :
  * 15kHz means 640x480i. For a reason that I ignore, my 31kHz couldn't display either the resolution (never had that problem before, but I hadn't tried such a setup for a while). And I noticed the kernel trimmed the available resolutions on the 31kHz and just left anything lower than 640x480 ... weird ... Anyway it explains why your LCD doesn't display anything : it can't do 640x480i
  * you're not on full analog displays
  * 640x480i is perfectly readable on a TV, so you're probably not at that resolution, as anyway the dialog should bigger
  * Did you hear GroovyArcade talk to you while detecting screens ? When testing the HDMI, did it say "Found a LCD or modern CRT" ?
  * for NVidia GPUs, I strongly recommend you use the NVidia setting, not the 15kHz. The reason is that the Nvidia driver rejects any resolution with a pixel clock lower than 25MHz, and the Nvidia option sets a 1280x480i which is fine regarding the pixel clock requirement.
  * you're using a HDMI transcoder which could also have some limitations (HDMI pixel clock is supposed to be > 25MHz)

I think we get a clearer state of the situation : you used the 15kHz setting, the kernel rejected the resolution, and set a nother one and your transcoder made wonders converting the video back to 15kHz. that's the most probable scenario. So what you should do is try the Nvidia option and tell me how it looks like.

Here is an old video (the detection is slightly faster today, but overall it's pretty much the same that happens) I made a while ago where you can see all steps with a perfectly readbale 640x480i on a CRT using the DVI-I output + DVI-I to VGA + VGA2SCART cable



EDIT :
OMG I've just noticed you are not using MY iso but the old one from VeS (which is not maintained at all, just drop it) ... Try with this one : https://github.com/substring/os/releases/latest