Thanks for all those technical details! For anyone else who'd like a broader tour around the AS/400, I can recommend "Inside the AS/400: Second Edition" by Frank Soltis. I bought it used for just a few dollars and really enjoyed learning about the evolution of the platform from one of its original designers, even though I doubt I'll ever put my hands on one directly.
They were big and heavy but not as bad as you would think. They could fit under your desk and were regularly just run out of a closet somewhere. Of course there were also gigantic ones but that was mostly due to the quantity of disk and tape drives that were attached.
Being an ISV, the thing that sucked the most was all the variety of tape formats. The drives were expensive and the tapes were expensive. So for someone to try our software we had to put it on a tape and mail it to them. This was not cheap!
That's right. I bought the book for a few dollars, not an AS/400 system, though I'd probably find a decorative use for one if I found one that cheap. I look at eBay and Craigslist every so often for cheap used mainframes (or at least the front doors) that I could turn into a neat garage fridge.
