Currently I run 2 displays, a 1080p 27 inch 60hz display, and a little TV that I found in my house. I use HDMI for both but my graphics card (gtx 760) only has one HDMI port. I use a HDMI to Display port adapter for my second display (the little TV) but I heard HDMI can only display 24hz. If I use the display port adapter on my main display, will I be able to see over 24hz? I haven't done any tests or anything, thats why I came here so I could get a straight answer before putting too much effort into it.
I think you mean 240Hz not 24Hz. Most TV's are only 60 or 120 (Most cheap small tvs being 60) and the high end ones going up to 240. The thing is even gaming computer monitors are usually only 60 or 120 HZ (144 if you get a G-Sync monitor)
So the answer is no. Unless you need a 4K monitor you will not see a difference with HDMI or Display Port.