Dawn of the Personal Computer: From Altair to the IBM PC
Imagine a world in which all cars are like the Toyota Prius: four-door midsize hybrids. Sure, they aren’t bad cars, you can paint them any way you want and even modify some parts, but in the end you still just have a generic Toyota with a funky paint job.
That’s the world of personal computing today. It doesn’t matter if you’re running Windows, Mac OS, or Linux. Your machine is almost certainly using Intel chips at its core and almost everything else is fairly generic—even the world’s greatest case mod with water-cooled dual-Xeons and quad-SLI graphics is just a really fast PC.
This was definitely not the case 35 years ago. A quick tour of the Computer History Museum in Mountain View, CA, reveals machines that were as varied and unique as the companies that made them.
The microprocessors, if there even was one, were supplied by Intel, MOS, Zilog, RCA, or any number of other companies. Memory was static, dynamic, and shift-register. And without the Internet, programs were loaded from paper tape, punched cards, cassette tape, floppy disks, cartridge, or even manually switched in by hand.
In the following pages, we take a close look at some of the most influential personal computers of the past 40 years. From pre-microprocessor machines to the venerated IBM PC, each of these systems contributed in some way to the modern personal computing era.
Special thanks to Erik Klein and the Computer History Museum for allowing us to photograph these artifacts from their collections.
Kenbak-1
Widely considered to be the first true personal computer, John Blankenbaker’s $750 Kenbak-1 had almost everything a modern computer has: I/O (lights and switches,) memory (256 bytes of shift-register memory), and a full set of op-codes. Missing were storage and an actual CPU; the Kenbak pre-dated the microprocessor by more than a year so the logic was implemented in discrete transistor-to-transistor logic (TTL).
The machine, designed by engineer John Blankenbaker, sold for $750 from a tiny ad in the back pages of Scientific American magazine at a time when a new Ford Pinto could be had for a cool $2,000.
Only a few dozen were ever built and many were used to train mainframe programmers.
RAM 256 Bytes
CPU No CPU (logic in TTL)
Supporting OS None
Predecessor Early mainframes
Successor All other PCs
Notable Firsts By most accounts this was the first PC
Xerox Alto
Xerox’s Palo Alto Research Center (PARC) was the source of numerous computer innovations including the mouse and the windowed graphical user interface. The company’s Alto system was never a commercial product but it did incorporate most of the aspects one expects from a modern computer: mouse, hard drive, networking, and a windowed GUI represented on a bitmapped screen.
Xerox built thousands for internal use and donation to various educational institutions.
Both Bill Gates and Steve Jobs were given demonstrations of the Alto’s (and the later Xerox Star) user metaphor and both went on to design their own versions for commercial sale.
Xerox eventually tried to capitalize on the technologies with the Xerox Star, released commercially in 1981, but the system was expensive and sold poorly.
RAM 64K-256K words (128K-512K bytes)
CPU Proprietary 16-bit
Supporting Operating Systems Alto Operating System
Predecessor Various bits of Xerox PARC research
Successor All GUI based PCs
Notable firsts First GUI, first Mouse
Scelbi-8
In early 1974 there weren’t many microcomputers available, but in March of that year, SCELBI (Scientific, Electronic, Biological) introduced its $550+ 8 series, based around the Intel 8008 microprocessor. Offered were the 8h hobbyist kit and the 8b business computer.
In addition to the machines, SCELBI produced some programming books and software. When the company realized that the documentation and programs made more money than the machines, it quickly adjusted its business model and abandoned hardware sales.
RAM 1K to 16K
CPU ~.5MHz Intel 8008
Supporting Operating Systems None
Predecessor Early mainframes/Mini-computers
Successor Other Intel-based personal computers
Notable firsts First microprocessor-based hobbyist PC
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john00998745566878
April 01, 2010 at 4:11am
How long have you been in this field? You seem to know a lot more than I do, I’d love to know your sources!
http://www.inkworks.com.au/
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john00998745566878
April 01, 2010 at 4:09am
A good read, definitely worth a cut and paste. Thanks!
http://www.ink2go.com.au/
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Wily_One
July 28, 2009 at 11:20pm
The Apple ][ was the first fully assembled personal computer. (based on release dates it preceded the PET and TRS 80.) You seem to be giving the PET extra points for having the built-in monitor. The Apple ][ could simply be hooked up to a TV. One key difference between the three is the Apple had color. The PET and the TRaSh 80 were B/W.
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gustyk
June 08, 2009 at 2:38pm
...was a Texas TI-99 4A with a glorious Extended Basic cartridge that allowed to invoke sprites that were 8x8 or 16x16 bits. I still rember how bad the function CALL COINC worked to determine when 2 sprites colide (vital for shooting games I used to program). The video procssor got dizzy with 3 or more sprites in line.
When all my classmates were dating girls in highs school, I was spending hours in front of the TV coding 16Kbytes of software... AAAGGHHH
My next computer was a Commodore 128. I learned how to trick some interesting features with PEEK and POKE. The most useful was the one that allowed to run C64 games with the power and speed of C128. My first lines in Assembler were written in C128...what a orgasm !!!
Then I jumped to PC XT, PC AT 286 with the 80287 math co-processor! Wow... Running Mathematica was such a pleasure...
Thank you MPC for the flashback!
gustyK!
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AMD64Blondie
June 05, 2009 at 8:39pm
While most of my PC is modern,the keyboard I'm typing this on is a 1991 IBM Model M.Sure feels just like a old-school PC.It's quite funny to think that the IBM Model M I'm typing on came out when I was only 8 years old.(my Model M was made in 1991,I was born in 1983.)With the right adapters(if needed) I think I'll still be using the same Model M keyboard 5 years from now.
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Asterixx
June 05, 2009 at 5:22am
Nunc est bibendum!
For an idea of what that hardware cost back in the day, I've got the entire 1983 Tandy computer catalog scanned and stored online. Simply go to http://www.foxthundercats.net/images/radioshack/page4.jpg (there are 40 or so pages, just change the page number to view the different ones). The prices for what we now look at as laughable technology will astound you.
I was disappointed to see no mention of the TI99/4A. That's the first computer I ever sat in front of, back in grade 4, at the brand new computer lab at Smokey Drive Elementary. We played around with Logo. The ol' 4A had a more imaginative way of dealing with errors - instead of DOS's staid "Bad command or file name" the 4A would say "Tell me how to ...". For example if you typed in "drw" instead of "draw" the machine would say "Tell me how to drw". Being a bunch of 10 year olds I probably don't need to tell you we had no end of fun coming up with funny things to type in so the computer would ask us to "Tell me how"...
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billcipp
June 04, 2009 at 5:43am
Let's face it. A lot of us started with Commodore because it was cheap and because we could program video games into it.
As now, back in the early 80s my friends and I frequented game rooms. Back then, alot of games were controlled with mechanical rotating parts and light actuated sensors. Then there was Pong. We were blown away! More and more computer games were introduced at this meeting place of early geeks and we became hooked.
My first computer was a Vic 20 mainly because it was under $300.00. Wow, not only my own gaming platform but we could program it. I learned quickly how to write and work with Basic. Then, we graduated to Commodore 64. Not only could I play the lates games and write my own programs, but I could actually use this computer with a program called GEOS for word processing and spreadsheets. Even my 3 year old son knew how to write the commands to start the computer and load the programs to play his favorite spelling and vowel adventure games.
Now I build my own systems, again because I can save some bucks and I know what I want; and I feel pretty comfortable about solving most of my families and friends computer woes. But, most of them take the PC for granted, like it was always there. I don't! I know how things started, and how things are today. Look at the graphics of the latest games, the cpus' and gpus', overclocking, etc., presentation capabilities, desktop publishing, digital imagery, not to mention the internet, facebook, instant messaging, etc.
To think, at least for me and my friends, it started with a simple game called Pong and a little computer called Vic 20! If the automobile progressed similarly, we'd all be riding in Jetson cars. What's that? Who are the Jetsons?
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EdwardVirtually
June 04, 2009 at 2:15am
as some have pointed out, a number of historically significant machines are missing. the timex sinclair, the vic-20, the radio shack color computer, etc. and before anyone gets too sad for old bill and his letter, it should be remembered his company's success is mostly due to his using a stolen copy of Digital Research's CP/M86 and relabeling it as his own product which he sold to ibm. he only cared about theft when he was the one being stolen from. doing it himself he had no qualms about. rip, Gary Kildall. you will not be forgotten.
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ironsmyth777
June 03, 2009 at 7:02pm
Haven't seen a lot of these in forever. Interesting, though a time line is definitely called for. My old favorite was a Tandy 1000 TL2 with a 10 MEG hd, 640 k (yes k!)) of ram later upped to 768 k(video would use the extra 128 k), and a 80286 (8mHz) Intel cpu. This rig got me through many papers running DOS with Desk Mate, a Pro-Write word processor, and a dot matrix printer. I still miss that thing from time to time. That sucker would boot in seconds!
"You don't build a reputation on what your going to do."- Henry Ford
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mono
June 03, 2009 at 5:54pm
How can you write an article of this type and not include the year each PC was introduced?
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pcwizmtl
June 03, 2009 at 2:53pm
again an again!
My first PC was a commodore 64, I was 3 years old at the time trying to match the letters in the book to the ones on the keyboard (lmao) at an attempt toprogram my own games!
thanks for the flashback MPC! :P
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ECA
June 03, 2009 at 12:15pm
lets get a few things STRAIGHT.
In the days of the C64, MOST programs were released to ALL the formats and machines.
the C64 was some GOOD office programs for its time.
Look up MULTIPLAN..
Look up the ORIGINAL GEOS.
The AMIGA FORCED MS to jump on the Graphical band wagon.
Before the amiga, MS/intel was more OFFICE oriented..and the graphics SUCKED until win 95.
The Amiga was popular in the USA, with those that LOOKED at what they were getting, and understood that Stereo sound and GRAPHICS were better on the Amiga. You also didnt need a MONITOR, just use the TV. there was no reason to spend another $200 for a 8" monitor when a 24" TV looked ALOT BETTER. And do I have to mention that theAmiga with the Video toaster and the Video FLyer PUSHED the video industry into Where it is now? And that the intel/MS machine couldnt beat the Amiga for 15 years running, until better graphics and the P2 MMX 200mhz came out. Beating the Amiga running on 35mhz, 16 megs, and 512k graphics.
You didnt even touch, BeOs hardware/software, which was mostly a rendering engine. This is so Two sided to a multifaceted history.
Im sorry that you were held in a box most of your young life.
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Boboche
June 03, 2009 at 11:25am
I don't know if this is funny, ridiculous, or just plain sad, but putting Apple I, II, III, and so on, you might as well have put the VIC-20, the Texax Instrument 99-4a and the Amiga 1000. As a Kid, these were the 3 computers (with the Commodore 64) that influenced me the most.
While I agree with the beginning and historical approach up to the PET, the rest is just extremely biassed, if not, the VIC-20 would have been there as much as the Apple 1 or 3 deserves to be there, heck, even the commodore 128 while at it. And what about the amiga 500 and 2000 which were huge hits, 500 for home gaming, and 2000 with the video toaster?
Were you around when the Amiga 500's arguments that were against it from the PC crowd were "well.. amiga is just good for GAMING... it's not a real computer" (exept for the fact that it had 4096 colors vs 4 on the PC, a GUI Multitasking OS that was fitting in less than 512Kb, separate graphic chipset that was offloading 2D calculation and having 30FPS video on-screen while the PC was smearing like crazy in 4-color graphic intensive applications, plus amiga had 3d animation software, amazing painting and video apps!
Just to prove my point, (yes I might have been an amiga fanboy back in the days) I would also put the Atari ST up there (amiga's biggest archrival back in the days), for Music, it was awesome and I'm sure some musicians here will point it out.
That mac classic without any amiga mention is a joke, you could pop Shapeshifter in your amiga and emulate that mac a 110% of it's speed, thus having both computers running, multitasking just as if you were running it on VMWARE by today's standards, AND running it faster than the equivalent mac (up to a quadra with a 68040!) since the bios was cached in fastRAM, making the Apple computers look overpriced and under-performing in comparison since the amiga alone was cheaper.
So how's that for technology and changing the way computers are being used? Did I mention stuff up there that are god awefully similar of what we see in PCs today?
I know about Macs and I validate the apple 2 contribution in the computing history, and the MAC classic was also a worthy piece on which I did a lot of paperwork, but for god's sake and transparency, dillute that Apple Fanboyism a notch, it's seriously irritating.
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mrvander
June 03, 2009 at 11:24am
I thought the predecessor to the Commodore 64 was the VIC-20? I clearly remember seeing a white VIC-20 at a friend's house shortly before I got my very own C64.
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canbbb
June 03, 2009 at 9:35am
As I understand it, the Amiga never got off the ground much in the Americas, compared to the very loyal cult following it maintained for years in Europe. Nonetheless, the Amiga was the first PC to introduce advanced video imagery to the consumer market - it was in the mid '80s if I remember correctly. It had great graphics, and games/software were quite available. Its marketing was obviously not strong enough to compete against the IBM PC and Apple.
I owned an Apple ][ back then, soon followed by a Mac+, but I remember envying my friends who had much more powerful Amigas.
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alloyking
June 03, 2009 at 5:08am
Some of you guys must be around some crazy Mac fanatics?? As bashing Mac fanboys was not my first response after reading this feature.
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Cache
June 03, 2009 at 5:30am
I personally don't mind Mac's, but some of the fanboi's are.... well, the Taliban thinks their doctrine goes too far, and that's really saying something.
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linkmaster6
June 03, 2009 at 5:52am
Thats a good one. I'm not saying Microsoft doesn't have its flops and its far from perfect but we Bill Gates shit does stink.
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Cache
June 03, 2009 at 7:31am
I'm fairly centrist on overall computer applications. Both sides have flaws, and both sides have definite perks. Ultimately, though, I find Apple's "Our way or the highway" mentality when it comes to computer applications to be somewhat closed-minded. I don't like the idea that merely replacing a battery voids any warranties on a product because it was deliberately made to fail--I find that very distasteful, and degrading to those of us who don't mind taking out what's there and upgrading to better parts.
Again, not saying that Apple does not have some very fine, fun products, but at the end of the day for me, I'll marry Microsoft and use Apple as my mistress.
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linkmaster6
June 03, 2009 at 5:25am
No just after reading about Xerox's machine it reminded me of arguments I've come across online where they were claiming they were. I really don't give a crap about mac fans blind faith.
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linkmaster6
June 03, 2009 at 4:10am
Well Mac fan-boys theres the proof you didn't come up with a GUI
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Havok
June 03, 2009 at 4:22am
They've been so blinded by anti PC and Apple propaganda that they can't accept what is in the history books.
OMGWTFBBQ
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paragonjr
June 04, 2009 at 2:14am
Of course, we all know that "history" books on any topic are NEVER biased! And neither are M$ fanboys! Even IBM couldn't compete in the PC arena. Lenovo or Acer anyone?
http://en.wikipedia.org/wiki/Lenovo























