I see in the news that Ken Olsen has died. Although he was not a crystallographer I think we should stop for a moment to remember the profound impact the company that this man founded had on our field.
My first experience in a crystallography lab was as an undergraduate in M. Sundaralingam's lab in Madison Wisconsin. While I never had the opportunity to use them, his two diffractometers were controlled by the ubiquitous PDP-8 computers. I had more experience with his main computer, which was either a PDP-11/34 or 35 (Ethan help me out!). This was connected to a Vector General graphics display running software called UWVG. Having the least stature in the lab I got the midnight to 4am time slot for model building. The computer took about 10 minutes to compute and contour each block of map, covering about three residues. While waiting I would crawl under the DECwriter and nap. The computer would stop rattling when the map was up and that would wake me. When I joined the Matthews lab in Oregon they had a VAX 11/780. What an amazing machine! It had 1 MB of RAM and could run a million instructions in a second. It only took 48 hours to run a cycle of refinement with PROLSQ, that is, if no one else used the computer. These specs don't sound like much but this computer was really a revolution for computational crystallography. That a single lab could own a computer of such power was unheard of before this. It wasn't just that the computer had so much RAM (We later got it up to its max of 4 MB.) but the advent of virtual memory made program design so much easier. You could simply define an array of 100,000 elements and not have to worry about finding where in memory, mixed in with the operating system, utility programs, and other users' software, you could find an unused block that big. Digital didn't invent virtual memory, but the VAX made it achievable for regular crystallographers. Through most of the 1980's you didn't have to worry about getting your code to run on other computers - Everyone had access to a VAX. In the 1990's DEC came out with the alpha CPU chip which really broke ground for performance. These things screamed when in came to running crystallographic software. In 1999 the lab bought several of the 666 MHz models. It was about four years before Intel came out with a chip that would match these alphas on my crystallography benchmark and they had to be clocked at over 2 GHz to do it. Yes, Digital lost out in the competition of the marketplace, and Ken Olsen was pushed out of the company well before the end. But what a ride it was. What great computers they were and what great science was done on them! Dale Tronrud
