After reading all the input I updated the article at: http://chmss.wikifoundry.com/page/Compaq%2FConner+CP341+IDE%2FATA+Drive
where you will now find a picture of what is likely the first ATA drive, called “fixed disk drive with embedded controller” by Compaq J You might note that the article was approved by the CHM Storage SIG wherein it states: The major reasons that ATA has become the most successful disk drive interface are: 1. Ease of integration: the emulation of the WD1003 controller implementation in the PC/AT allowed booting without BIOS modifications, initially up to 528MB and subsequently to 137GB, although there were a number of other barriers to increased capacity that also had to be overcome along the way [16] 1. 2. Low host cost and complexity: by separating the WD1003 functions from the host functions, the cost of the host adapter was reduced to the point where it could be integrated first on to the motherboard and then into the “Southbridge.” 2. 3. Acceleration of technology advancement: Like SCSI and the other “intelligent” interfaces, this broke the “controller barrier” but IDE/ATA was the only one that also had the above two advantages, providing a significant reduction in time-to-market and enabling ATA to rapidly catch up to the high end areal density growth curve, where it became the disk capacity leader, with the lowest cost per GB. FWIW, the “controller barrier” is the delay in drive market acceptance required to design a new controller for a new drive interface. For SMD is was about two years. tom