HDMI is really best for connecting a PC to an HDTV. Consequently, I’d go with a DVI cable. That’ll give you a pure digital signal (VGA is analog) and a much sharper picture at higher resolutions.

For example, your TV likely has HDMI 1.4 connections, which max out at 3,820x2,160-pixel resolution at 30 frames per second. If you've gotten a new 4K monitor, you're limited to 30fps.