Modding DVD player

Just wondering if the aftermarket modifications (Trichord, Superclock, etc..) also affect the picture quality as well as sound.
No they do not but Power supply upgrades as well as changing the progressive scan caps on a decent player such as the Philips 963sa will show great results for the video section.

When compared to my Denon 5900, the modded 963sa was at least as good through 480p but whith less artifacts.
The 5900 is now sold.

I also have a Zenith LG 318 hd that upconverts to 1080i through component or dvi that will be modified for video along whith the digital section and power supply in the next 3-4 weeks.