I understand your pain. :X
Try using the next VGA mode after 640x480P that has Interlaced video scanning. I don't remember the mode, but it's the only one that uses Interlace scanning.
SCPH-10000 S. MINOKAMO v1.01 (Defunct)
SCPH-10000 S. KISARAZU v1.00 (faulty)
SCPH-15000 S. KOHDA (With warranty seal!) :D
DESR-5100 S. EMCS