Whats this video glitch then?? Any ideas appreciated!

[hooperjaws]

My machine does this weird screen glitch. It can happen (and rectify itself) when scrolling up and down in the menu in MALA (and the machine is making a click sound) and trigger when it is switching screens to start a mame game (and on reverse).
Is there anything worse in computing that intermittent errors??
Heres the glitch happening in both the menu and the game. It looks like every other raster scanline is offset by 10 pixels!!
Pic 1: My mala menu bein glitched.
Pic 2: Closeup of the glitch
Pic 3: Launched game being glitched.

My gut is saying its a windows issue, rather than a monitor issue.

System: Ancient PC running in a jamma wired cab (hantarex polo 15 monitor) using a J-pac. Radeon 9250 AGP card, terratec Aureon 5.1 PCI sound card. Soft15Khz, Mala, Cabmame.

Thoughts???

[Mike A]

Does somebody you know have a JAMMA PCB you can throw in there? You would have a better idea of where the problem is.

[hooperjaws]

Thats a good thought. Unfortunately, no. It did come with golden tee board (that was what the original machine was) but I have moved house twice since then and Im not sure I still have the board in my boxes "of bits".
I have had the machine on for two hours tonight and it hasn't done it once. Guaranteed it will again though , it seems a regular occurance.
Even if I find a jamma board theres no easy way of making it "happen" on cue.  I hate intermittent faults - they are the worst!

[pbj]

Cap kit

[buttersoft]

Can you remove the Jpac from the setup and see if that does anything? The image on the screen would be really dim and probably need ajusting to make it as bright as possible, but it might help.

[hooperjaws]

The PC graphics card plugs directly into the Jpac and that is where the monitor pics up the signal. I am not sure the monitor can take the signal direclty from the vga out of the PC. Ive also heard that the bios gives out 31Khz and might damage the arcade monitor - hence the Jpac offers a level of protection.

[pbj]

Bad connection or a dirty pot.  I’d reseat your connectors a few times and twist your v and h sync adjustments back and forth.