Plextor PX-755SA 16x DVD&plusmn;R/RW Dual Layer SATA Internal DVD Drive Double layer allows you to record up to 4 hours of high-quality MPEG-2/DVD video on a 8.5 GB disc AUTOSTRATEGY Writing technology for unknown media with uneven quality 2 MB cache and Buffer Underrun Proof Technology prevents buffer underrun errors Supports DVD+RW background format and DVDVR format for direct disc recording Horizontal or vertical mounting orientation