I don’t mean OS’s, I mean the actual computer. I have heard occasional mentions of other types, but assides from the standard Intel’s and Apple/Motorola machines, I really don’t know about any other kinds.
I’m not that much of an alternative hardware geek, but in my business settings I run into Sun Sparcstations and IBM RS/(crap - I can’t remember)4000(?)s that are running Unix. They’re usually a PITA.
And of course, you’ve got the AMD etc. Windows/Linux alternatives.
Sun, IBM, Compaq and HP all have their own machines which run their own flavour of OS. They tend to be servers - check out their websites for information.
While I was attending Red Deer College, they were running their network off VAX/VMS servers. As I far as I know, VAX is the hardware, and VMS is the operating system.
We were using the system to create, compile and run COBOL programs, so I got a lot of exposure to it… Kind of intimidating at first, but it grows on you!
Though you don’t see them as much anymore, SGI is still chugging away making their machines. Those are also mostly Unix systems.
Every few months whomever owns the Amiga license that week threatens to release new hardware, but I’ve never heard of any of those coming out of the vapor phase.
Didn’t Gateway scarf up the remains of Amiga, probably never to be seen again?
And yes, Silicon Graphics (SGI) is still around, and last time I looked they’d gone Intel.
The first “off the shelf” computers were made by Digital, and were called PDPs (for Programmable Data Processor, since they thought the term “computer” would scare people since computers of the day were so expensive). The PDP computers were very popular in the 70’s. They ran RSX and Unix as their two most popular operating systems.
In the 80’s Digital replaced the PDP with the VAX, and replaced RSX with VMS as its primary operating system. The VAX was replaced by the Alpha in the 90’s, and fairly recently Digital was bought out by Compaq and the Alpha’s are pretty much dying out. Alphas ran VMS and Unix, and there was a push to have them run a version of NT as well. When NT Alpha died, the Alpha kind of died with it.
There are a lot of unix computers that are popular. Most of the big ones like SGI and SUN have already been mentioned. IBM makes some pretty big servers. They like showing their latest slick desktop and their refridgerator sized computers together in some of their commercials.
Another noteworthy computer that hasn’t been mentioned is the Cray. Crays 20 years ago were the top of the line supercomputers. The funny thing is that desktop PCs have almost caught up to them as far as computing power is concerned. Crays were used in the earliest digital movies like the last starfighter and tron, and did a lot of the flow calculations when they were designing the space shuttle, just to give you an idea of where they were used.
So what is the difference between these computers? What seperates them from a wintel machine?
The IBM RISC series (Reduced Instruction Set Computer) was a good one. I don’t know if they’re still made. But the thing that made it different is that its CPU chip used a drastically reduced instruction set. The point was to simplify processing and speed it up.
The internal processor and architecture is different. For example, a “wintel” machine has an Intel x86 compatible processor in it, along with a bunch of support chips that all have to be in a particular configuration or else Windows can’t run on it. It is entirely possible to use an Intel x86 processor of some sort and put it into an architecture that is different (as is often done in things like industrial controllers and custom architecture computers) and then you can’t run windows on the machine.
Back in the 70’s, the way you made a “better” computer was that you made it able to do more things. The more complex and powerful the instruction set of the processor, the “better” the computer was. These types of computers have since been named CISC for Complex Instruction Set Computer. A Pentium is a CISC. Vaxes were about the ultimate in CISC. A Pentium, for example, can handle operations on bytes (8 bits), words (16 bits), and doublewords (32 bits). A Vax can do operations on bytes, words, doublewords, quadwords, and octowords. Vaxes were also designed to be multi-tasking and multi-user machines, so they have internal caches and structures designed just for this purpose. A Vax 11/780, which was common about the time the XT was popular on desktops, has about the same performance as a 386 if you just use it single user. But, if you use it multi-user, it performs about as well as a 486.
The Alpha and many other later computers like the Sparcs are RISC processors (Reduced Instruction Set Computer). The idea behind RISC is that you have a processor that is stripped down to only the basic functions, but then you take these stripped down functions and use simple hardware to make them go very very fast. For example, a Pentium can, in one instruction, add two numbers together and store the result somewhere in memory. In a typical RISC chip, you can add two numbers together, but you can’t store it in memory all in the same instruction. RISC chips are harder to program, but they force you to do things in an efficient way. They also take advantage of “pipelining” where each step in the process is done by a seperate section of hardware, so you shove instructions in one end of the processor and they get processed piece by piece by different sections, then pop out the other end of the “pipe” when they are done. The whole idea of RISC pipelining works so well that even CISC chips like the pentium will break down the instructions into a smaller set of instructions and will then feed them into a RISC-like pipeline.
The Cray was a vector processor. It wasn’t so good at general purpose things like the Pentium, but give it a bunch of numbers to crunch and it could crunch them very fast.
Things that you take for granted on a PC may not be present on other computers. The IDE in an IDE disk drive stands for Integrated Drive Electronics, which means it is basically the architecture of an old PC disk controller built into the drive. It’s also called ATA for AT (as in IBM AT) Attachment. As the name suggests, it is highly coupled to the PC architecture. Later Alphas could use IDE disks, but more often they used SCSI. Vaxes used SCSI or DSSI (an older interface that was the precursor to SCSI), or sometimes strange interfaces that bear little resemblence to anything you might see on a PC like the SDI interface. The whole idea of “standard” hardware interfaces didn’t really come into popularity until the PC really took off. Most other computers use proprietary hardware that can’t be interchanged like can be done with PC stuff. Many computers can use SCSI disks. For a while, it seemed like PCs used IDE and the rest of the world used SCSI. Then when IDE disks became dirt cheap compared to SCSI, most computer manufacturers created an IDE interface to their system. I know that we were paying about $800 a drive for disk drives in an Alpha, and the same size disk was going for about $100 in a PC. On the other hand, 20 gig hot swappable (you can take the drive in and out while the computer is running) disk drives worked very well in an Alpha, but I’ve never seen the equivalent on a desktop PC.
The internal connections were also different. In a PC, you have had the ISA bus, MCA (in the old PS/2 computers), VLB, and PCI. In other computers you will see things like VME, multibus, Q-bus (in the old vaxes). Similarly to disk drives, PCI interfaces are becoming common in other architectures, if only because the components are so much cheaper. These architectures always end up being a little kludgy, because if you really look at the specs the ISA interface is basically the 8086 processor bus, VLB is very close to the 486 processor bus, and PCI is very close the Pentium processor bus. If you don’t have these types of processors in your system, creating an interface to them gets a little messy.
We probably should mention that the mid 80’s was the heydey of the “minicomputer”, typified by the DEC VAX which has already been mentioned. Vaxes, often comically pluralized “vaxen” were the mainstay of the early internet. Mostly running BSD UNIX. DEC brought out its own UNIX flavor, Ultrix, in addition to VMS for its machines, but it never really caught on.
The company I worked for in that era ported their product to a huge number of machines / OS’es (something that I always thought was a bad decision - somebody would dangle a little money in front of them, and a-porting they would go). Let’s see:
Pyramid - well, they LOOKED cool.
Sequent
CCI (Computer Consoles International)
Gould
Data General - !@*$!#**!
AT&T 3B series - now, THAT was a roaring success
… and more that I can’t recall right now.
We had a machine room that contained quite a menagerie, since a lot of these vendors gave us a machine for the porting effort, and we continued to use them. A couple CCI’s were our main file servers for a long time. My particular group used one of our Pyramid’s.
Pyramid made their money in those days by making a VAX class machine that cost a lot less.
Oh, then we had Prime, Wang (which actually used “Want to see my Wang” as an ad slogan for a while) and Tandem in those days.
Modern day companies - I don’t think anybody has mentioned Fujitsu yet. Fujitsu manufactures some high performance supercomputer stuff, as well as the Wintel notebooks you probably associate them with.
This page is annoying but has good information about CTOS/BTOS machines. Look at the pictures to see these bizarre contraptions. This hardware is still being used after 23 years. I can tell you from experience that the US Coast Guard still used this Unisys supported equipment on a nationwide x.25 network until it was finally phased out in 2001, not because the hardware and software was outdated, but because of the high cost of maintaining the x.25 network. I suspect that there are pockets still surviving out there, like silicon coelocanths.
Darn. That’s “Computer Consoles, Incorporated”.
One place you might look for non-garden-variety machines is on the list of supercomputers. A “top 500” list is maintained:
http://www.top500.org/list/2001/11/
A new list is due in a couple weeks. You’ll note Compaq appearing in there - they bought DEC several years back - somebody’s already mentioned the Alpha.
Just to nitpick, but I should also point out that there are numerous other “specialty” embedded computer processors, usually used for dedicated tasks like controlling your microwave, making your cel phone work, and managing your VCR. I’d cite some names, but I’m feeling lazy. 
I’m not exactly sure who owns Amiga at this point, but this is the most recent slasdot article I could find about them: Nokia Set-top Boxes to Ship with AmigaDE. It’s from February
As for SGI, they ended their foray into commodity hardware a while back, and are back doing what they do best. Though they have some cheaper “budget” systems that run linux on itanium, most of their offerings have gone back to MIPS systems running IRIX.
PIC, 8052, MC68HC11, Basic Stamp…
I’m lazy too, but I do this for a living and those are the names I can think of off the top of my head.
Don’t forget Palm, Pocket PC and Psion. They are real computers. My Palm has more processing power than my first PC.
As for embedded systems, don’t forget the good old Z80 processor. They are still in use. I had to program one last year.
At the university I’m going to, they still use VAX dumb terminals in the labs that have high magnetic fields, because the dumb terminals dont have disk drives that would get rather messed up by the fields created by NMR machines.
On the x86 side, there is also Transmeta and Via making processors for notebooks and desktops. Back in the 486 days, there were also a lot of Intel Clones around.
Motorola and Texas Instruments are very big in the integrated microprocessor world (the computers in things that arent computers, ie VCR’s)
And then there is the Sony Emotion Engine and the Nintendo whatever which are game consoles but would probably still be considered a form of computers (you can get Linux on the PS2).
Someone mentioned HP having it’s own OS but that’s not really true. The MPE operating systems was distinctly HP but I don’t think there are many of those boxes around. When I worked at Biosphere 2 we had accounting on a micro 3000 “Mighty Mouse” box but it was obsolete even then. Most current HP systems use their PA-RISC processor and run an HP flavor of Unix, HP-UX. Keep in mind there is more in common with various flavors of Unix/Linix than there are differences so I don’t consider them to be different OSs (OSes? Oh-Esses?). It’s a bit misleading to say Unix is a server OS as the only real difference between a Unix server and a workstation are the features and capacity of the hardware.
You mention “Apple” as one kind of computer but that’s very misleading. The original Apple II family used a 6502 processor. Can’t remember what the IIGS used. Macs started with the Motorola 6800 family of processors and now use the Power PC and very different hardware architechture than the originals.