Anyway, so I just got VGA working on my PS2. My monitor supports sync-on-green, so I only had to wire up red, green, blue, and ground to a VGA plug. Here's what I noticed:
- Only works with progressive-scan games. Won't work with interlacing AT ALL.
- Quality is vastly improved over composite.
- Lag is noticeably less than using a USB TV tuner through my computer (my previous solution).
- Not all games support progressive-scan.
For now, I'm just going to enjoy finishing God of War II in wonderful clarity over VGA.
Edit: After a few hours of researching this, it seems that I've run into the typical DIYer problem: there ARE deinterlacer chips available, but they're only available in huge quantities. One chip I found is the ABT2010, which supposedly has RGB, composite, HDMI, and S-video inputs with HDMI output. It scales and deinterlaces, which is exactly what I want. But I couldn't find anywhere that stocks the chip, and the evaluation board seems just as difficult to find.