How much time does it take to write an HD DVD-R, HD DVD-RW, or HD DVD-RAM disc?
HD DVD-R and HD DVD-RW specifications define 1x CLV writing and for HD DVD-RAM 1x ZCLV. Since 1x HD DVD writing transfers 4.36 MB (4,568,750 bytes) of data per second it takes, roughly, 55 minutes to write a full 15 GB (single-layer R/RW) disc or 74 minutes for a full 20 GB (single-layer RAM) disc.