That's 1.5x more pixels then 4k, take a look at the 4k FPS and divide by 1.5, that will give you the types of FPS to expect with 3x 1440p monitors.
yes, it can run 3 of those monitors just fine
no it won't game on all 3 monitors at all. pick a monitor and game on it, cause it's fine in 1440p. for some titles you might be ok with 2 of those monitors. But you'll probably be unable to game on all 3 at once unless it's a very old game.
heck, 2 1080s can't even game on 4k reliably with top spec titles.