Can't export HD videos in FCP

Hi there! I'm having trouble when exporting any video from Final Cut Pro 7.0

Whatever Settings I set for the sequence or format I choose to export, my video will look horribly, with lots of pixels and nothing like HD videos I can export using the same configs in the other MAC here in the office.

I've set boths FCP exactly the same, I've chosen the same exporting format, but the final video is really different in the two MACs. I don't know why I can't come up with the HD video in this one.

Do I need any codec or plugins to have a successful export? What's happening?

Thanks In advance!