Well, there are some limitations here and there, but the skinny on it is as follows for 4k support:
HDMI: HDMI 1.4 will do 4k, but is limited to a maximum of 30fps. That applies to either games or video content, as that's the maximum that it can refresh the screen at. If your 980ti has HDMI 2.0, and your TV supports HDMI 2.0, then you can do 4k @ 60fps.
DVI: There are several flavors of DVI, from DVI-A (analog), to DVI-I (mixed output pins) to DVI-D, and DVI-D DL (Dual Link). In general, DVI in a single link format can only do a maximum of 1920x1200 @ 60fps, DVI Dual Link can do up to 2560x1600 @ 60fps, it would require (don't ask me how this would connect) - two DUAL LINK DVI cable setup for 4k @ 60fps.
DisplayPort: DisplayPort v 1.2 can do 4k @ 60fps. However, TVs generally don't have display port connections, those are only found in 4k monitors, so it depends on what you're connecting the computer to.
Hope that helps sort it out.