thx skate323k137, but the problem is BVM 20G1U dont have extsync input, just RGB IN/OUT and "IN" and "OUT" (Y/R - Y/B - Y or RGB analog component inputs included as standard):
http://i392.photobucket.com/albums/pp4/mccominc/Mccom%208/IMG_3626.jpg
neo geo cable that's ok? maybe "IN" is a...