More information, please. Are you trying to record over-the-air HDTV broadcasts? Are you trying to capture live video from a High Definition video camera?
You mention "tuner cards", so I assume you are asking about PC hardware, and yes some inexpensive television tuner cards can be used to capture analog TV or video signals, but I would hardly call that "HD quality". Likewise there are a few true HDTV tuner cards - some will allow spooling the HDTV bitstream to hard disk, and offer playback indistinguishable from the live broadcast.
It is hard to answer a non-specific question. The better your description of what you want, the more the Forum members can help.
Gary
You mention "tuner cards", so I assume you are asking about PC hardware, and yes some inexpensive television tuner cards can be used to capture analog TV or video signals, but I would hardly call that "HD quality". Likewise there are a few true HDTV tuner cards - some will allow spooling the HDTV bitstream to hard disk, and offer playback indistinguishable from the live broadcast.
It is hard to answer a non-specific question. The better your description of what you want, the more the Forum members can help.
Gary