15khz working in game but not in menu or GroovyArcade setup

[TTretrogamer22]

Hi everyone,

I recently aquired a candy cab with a 27" CRT CGA. It came with a 60-1 jamma game board but sinec owning it I decided to install GroovyArcade/MAME linux on an old pc.

I'm using an old i7 4770, 8gb ram and ATI 5450 card with VGA. DVI and HDMI, and J-Pac

When installing through the LCD option at start up I have no issues, but when trying to switch over to the CGA, I get no image, until i start a game. When i start a game and have the pc connected to a CRT PC monitor, the image goes nuts. Once this happens, I connect the CGA monitor to the PC via the J-pac and i get a clear image ( of the game) without any issues. When i quit the game, I lose image. Obviously, the resolution and screen settings are off - set for LCD.

Realising this, I attempted to reinstall and select 15hkz at the setup. I did this buy having the PC monitor on through setup and having the 15khz option highlighted, then switching to the CGA monitor and selecting enter. The screen goes a bit haywire, like a vertical sync issue but can sort of make out a installation message, then the screen goes black. This happens twice and the screen stays black.

Just wondering if anyone could point me in the right direction? if the computer is able to send the right signal through when playing a game, why would it not work any other time, like the menu or during setup? 

Thanks heap in advance!!!

[Substring]

Use a LCD only to reach the boot menu, highlight the desired option, then unplug it, plug your cab, press enter, and let the magic happen. This whole configuration is made for the target monitor, not the current plugged monitor. Failing to do so results in numerous configuration errors that can be manually solved if you know Linux. Otherwise, you're good for a long session with me. Or reinstall.

[TTretrogamer22]

Thanks for the reply. Thats exactly what i've done. I use an LCD to get it to the point of setup/choosing a screen type, disconnect, then connect the CGA monitor. I make sure I have the 15khz option highlighted prior to disconnecting the LCD and connecting the CGA. Once I have connected the CGA, I press enter - to select the 15khz option. I do get some sort of image, but it doesnt last logn and cuts out. I'm assuming it has something to do with that function of selecting 15khz and the screen + Jpac not liking it. I assume if the cga screen works with games, it seems safe to assume it must be working fine, just not at setup or Groovy Arcade

[purbeast]

Have you tried adding the resolution of 320x240 to the ini file that VMMaker loads up?

I never had your issue where it went black and wouldn't work, but I did have to add it to mine in order to run my desktop in 320x240, which is also what I run MAME in with a CGA monitor.  My monitor can also do 640x480 interlaced but it doesn't look as crisp as 320x240 progressive. 

I don't have much knowledge at all with this stuff but perhaps give this a try so your desktop can run in the same res at MAME does?

[Substring]

Use a LCD only to reach the boot menu, highlight the desired option, then unplug it, plug your cab, press enter, and let the magic happen. This whole configuration is made for the target monitor, not the current plugged monitor. Failing to do so results in numerous configuration errors that can be manually solved if you know Linux. Otherwise, you're good for a long session with me. Or reinstall.

Did you answer to the questions when GA is testing the various gfx card outputs ?