The answer is – whichever cable is least expensive.
HDMI cables are designed for connecting HDTV’s to other devices, like your cable box, Blu-Ray player, XBOX, PS3, or your computer to your monitor. HDMI cables cost anywhere from $5 each (or less, if you find a sale) to $100 each. The difference between expensive HDMI cables and inexpensive HDMI cables is hard to detect. Since the cable is carrying a digital signal, it either works or it doesn’t – you won’t find a difference in the picture quality. Brand name cables may be slightly thicker, having more shielding around the cable. If you have a pet that chews cables, you’ll probably want to get a few of the $5 cables, since they’ll eventually chew through a thicker cable.
There are HDMI cables with different names – standard speed vs. high speed. Standard speed handle 1080i, and high speed handle 1080p. And now, a brief lesson in the difference between those …
1080 refers to a resolution of 1,920 pixels by 1,080 pixels. The “i” refers to the picture being interpolated – the picture is drawn by creating all the scan lines in order of odd lines, then even. The “p” refers to the picture being progressive, and creating the picture from top to bottom. Typically, the progressive is better for fast paced action – but unless you have an enormous picture (like a projector with projector screen) you’ll be hard pressed to notice the difference.
Save some money by not buying expensive cables, and make sure you buy a couple of extras if you can.