At what resolution?
At the FCPWorks LA demo one MacPro Tube was outputting 3 streams of full 4k ProRes 444 to a big Christie in real time. But i didn’t see 4.
But if you’re just looking for a standard display of quad 1920×1080 rasters I doubt X would even break a sweat.
I have a friend who does big time convention iMAG stuff and he does live super wide multi screen work at around 10,000 pixels x 1080 via X to multi screen arrays. And he plays those out off an SSD equipped MacBook Pro.
Just set a custom raster Storyline in X and drag and drop your video(s) into place.
The only warning is that if you do use high Rez sources, X can take a LONG time for rendering out composites, cuz it doesn’t “dumb down” it’s compositing math.
FWIW.
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