Viper Phase 1 video problem

So, I finally got to put some boards into the JAMMA cocktail machine I modified today and everything went smoothly except for my Viper Phase 1 board. Basically, everything seems to work except for the video. The sound is clear, the game responds to inputs, etc. Unfortunately, the monitor shows nothing but small white lines scrolling very quickly (they look like shooting stars, actually) and sometimes colored diagonal stripes wiggling around. The color changes seem to correspond with the action that should be going on on screen. I've cleaned all the JAMMA contacts on the connector and board with no additional luck. Any ideas?

Rrom your description it sounds like a sync issue. The SPI board that runs V:P1 outputs an unusual vertical sync, 54Hz IIRC, and it's possible your monitor is choking on this. There's nothing you can do if this is the case AFAIK.

If it's an actual RGB arcade monitor you could adjust the horizontal or vertical sync and see if it will lock on.

It is an actual RGB arcade monitor (in a real cabinet, too).

After adjusting the H Sync as far is it would go in both directions of turn, I still came up with nothing. The patterns would change, but I was never able to lock onto any solid images (not even close). I'm guessing this is still likely to be the problem, but it doesn't seem like my adjustments are doing the trick. Any other
insights? Thanks!

try to disconnect the cartridge from the motherbord , blow out all contacts on both the motherboard and the cartridge . Maybe it got jammed in shipping .

maybe not your monitor but see if it helps .
http://www.arcaderestoration.com/index.asp?OPT=3&CBT=24

My monitor is a Wells Gardner 19K4606 (if that matters to anyone). I was able to locate the other sync adjustment that's shown in the link above (thanks!). After messing with that for a while, I've managed to lock onto a pretty solid image of the game, but there's still a problem. All over the screen, on top of the game's graphics, there are many wiggling patterns that look like dotted white sine waves. While the game is "playable" now, it's distracting and ugly to have all these waves moving across the screen. I've played with all the other adjustments on the monitor and can't seem to make them go away. Should anyone be interested, I can provide a picture upon request if that might help. What's my next move? We're definitely seeing progress.