"Real Computers" (was Re: Trivia Question)

I wrote: Phil wrote: Even if it's the dual Athlon XP 1900 running Red Hat 8 which I use for most of my software development. There's no question that it has orders of magnitude more computing power, memory, and disk, but that's not part of my criteria for "real computer": 1) Is it well-engineered from the ground up? PCs: no, a lot of the stuff in even the best PCs is of very poor quality manufacture - even the non-high-tech stuff like the cases are shoddy. 2) Can it be expected to have a long operating life? PDP-8: I've got one that is 27 years old and still works great, largely because it was well-engineered. Do I believe that PCs made today will work 27 years from now? Some will, but if you were to compare PDP-8s and PCs stored and operated under comparable conditions, not nearly as high a percentage of PCs will survive. 3) Is it documented? PDP-8: very well PC: barely at all. Just try to get information about what your BIOS does in System Management Mode - for instance, if you PC supports ECC, how do you get the error log? And forget about getting source code for the BIOS. Although the processors from Intel and AMD are fairly well documented (there are still some secrets, but not as much as in the Pentium Appendix H days), the "chipset" is often poorly documented or not documented at all. For instance, information on configuring the caches and memory controllers is typically not available, with the excuse that the BIOS does it for you. 4) Can it be repaired if it breaks? PDP-8: definitely. PC: no, you throw away a subsystem and get a replacement. The problem here is that any given subsystem (e.g., a video card) is only on the market for maybe two years; after that you can't get an identical replacement. Original-spec PDP-8 replacement parts were available for over 20 years. I'm not saying that PCs don't have their place. I use them all the time. But calling any PC-compatible machine a "real computer" is a sick joke. Eric