It seems that the original Xbox can be "forced" into Hi-Defenition mode. In the following video the user claims that the original Xbox can be forced into High Definition mode and allows all original Xbox games to be in HD, even if they were only meant for standard definition. Therefore the standard 480p games can be played in 720p and 1080i HD upscaled.
To connect the original Xbox to a HDTV you must have a High Definition AV Pack. High defenition is accessed via component cables, these are the best video cables for the original Xbox, HDMI is not accessible. The original Xbox allows up to 1080i HD. There are plenty original Xbox games that offer HD support as well as emulators.
*concerning the PAL region, your original Xbox must have a softmod installed to access HD settings
Instructions for forced High Definition:
- Enter "settings" from the Xbox dashboard
- Enter "video"
- Choose "normal" video mode
- Choose "yes" for 480p, 720p and 1080i
- Return to the Xbox dashboard
- Hold the following buttons together left trigger, right trigger, left analog stick (button), right analog stick (button)
- Your original Xbox is now in forced HD mode. The mode will remain even after shutting off the Xbox. To resume your Xbox to standard simply re-do the steps prior.
The following HD formats are supported for Gaming
480i/480p/576i/576p output at 480p (Not Scaled)
480i/480p/576i/576p output at 720p (Upscaled)
480i/480p/576i/576p output at 1080i (Upscaled)
*720p & 1080i resolutions are not supported, at any output resolution
Original Xbox Supported Video Formats and Resolutions
This is a comparison table of common video-codecs to show what the original Xbox 733Mhz PIII CPU and 64MB RAM can handle. Click on image to enlarge.
(click on image to enlarge)
Hold down the right and left trigger and click down the left and right control sticks to force the Xbox into HD.
High Definition AV Pack is the official way the original Xbox was meant to display high definition.
Shop for High Definition AV Pack at eBay
image via terapeak