In my project I'm using a CM2009 IC between precise VGA controller and VGA output connector. It is really stated during the datasheet for this IC that I can use EMI filters on HSYNC, VSYNC and DDC channels correct after IC and before VGA connector. However there aren't any specs https://dallaswurld.slypage.com/31755556/an-unbiased-view-of-emi-filter-for-led-lights