Reddit reviews Av-s Video Composite Cable for Nintendo 64 N64, Gamecube, & Super Nintendo Snes

I can't speak much on the NES but I've streamed the SNES plenty.

When you say "horizontal lines", does it look this this? That's interlacing, which is characteristic of older TV and consoles, and that can be fixed to an extent with software. Amarec is a popular program used to capture video, and it's able to de-interlace. If you're capturing directly with Xsplit or OBS they should have de-interlace functions too (though in my experience OBS's can be pretty cruddy unless they've improved it recently).

If you're interested in quality I also highly suggest getting an S-video cable. I'm not sure if the Dazzle 710 can capture S-video but my Dazzle DVC-100 can. According to Amazon this is the one I use with my SNES. S-video makes things look cleaner, gets rid of rainbowing effects and dot crawl.

Just a suggestion for the future, especially if you're not able to fix your problem and get a new monitor: get one with s-video inputs, and pick up a couple of s-video cables for your SNES and N64. The clarity they provide over composite is totally worth it. Depending on what kind of switcher you have currently, you may need to get a new/different one. But they're not all that expensive.

http://www.amazon.com/Composite-Nintendo-64-N64-Gamecube-Super/dp/B002GC68P6/

http://www.amazon.com/RCA-VH911-Video-Switch-Box/dp/B00008X5DE/

Av-s Video Composite Cable are the same for Nintendo 64, Gamecube, & Super Nintendo Snes

So if you got one from any of them?

If not, 1 dolla on AMZ

https://www.amazon.com/Composite-Nintendo-64-N64-Gamecube-Super/dp/B002GC68P6