1024x768 is not a HD resolution. HD (High Definition) standard valid for video broadcast specifies only 720p and 1080p/i resolution, where the first stands for 1280x720 and the second for 1920x1080.
A game cannot be HD, reasonable 3D engine allows you to set whatever resolution your screen and GPU support so please, stop using this meaningless marketing-made crap like HD when talking about games, or better yet, stop using it at all