Lines missing in certain games.

[Santoro]

I am missing lines in certain games.

[elvis]

Looks like you are playing vertical games on a horizontal monitor.  Due to the fact that these games where never designed for horizontal monitors, you will lose line information.

AdvanceMAME has a number of added blitter effects to correct this problem.  Documentation here:

http://advancemame.sourceforge.net/blit.html

[Santoro]

This is the first time I have used a vanilla arcade monitor, I used a D9200 last time.  I thought I has read a lot on the topic, but I missed this apparently basic fact. 

Thanks for the pointers.  I'll read up.