Computing power

[Allen Crisp]

I remember when I was a schoolboy, the maths master once asked "who wants to go and see a computer". So I did. This would have been about 1968. The computer occupied a large space in a local Government building, and was made up of a lot of tall cabinets. Data was input via punched cards.

How powerful would this have been, compared to modern small machines, in terms of speed and memory? Obviously I don't remember any of the precise specifications of it (if I ever knew them), but does anyone have a rough (or better) comparison between machines then and now? Or a link to a website with the info would be good - I can't find one myself.

[ChuckFickens]

They would have had less computing power and storage than a wrist watch these days.

here is the details of an IBM main frame of about that time

http://en.wikipedia.org/wiki/System/360

note things like "A large system might have 256 KB of main storage" (by contrast a 1GB hard drive is 1048576 KB)

computers of about that time would have been able to do about 60,000 instructions per second, modern computers a modern intel i7 CPU can do about 76,383 million instructions

http://en.wikipedia.o...uctions_per_secondper second

[ChuckFickens]

link didn't work!!

http://tinyurl.com/2mm4wr

[Jumbuck]

Those were the days - back at that time my maths teacher got a paper tape teletype for the school, so we'd write programs in basic (for doing things like calculating pi to 20 decimal places), type them up to create the tape together with listing, and every week/fortnight he would take us to a local college of technology to run them. You were allowed into the room containing the computer but you had to hand the tape to one of the technicians to load it into the feeder; however you could watch the results being printed out before they were handed over to you.

[VHG]

I used to work for IBM and I remember working on some old 370 mainframes.

The hard disks were HUGE (in size not amount of data).

Here is an example of how big they could be.

http://www.tpub.com/neets/book23/0066.GIF

I remember having to load the programs in the mainframe using punch cards (small cards with holes in them).

As Chuck says, I bet there is far more computer power in an MP3 player or your TV than there was in an old mainframe.

I remember working on one of these mainframes in early 1970s.

http://www-03.ibm.com...mainframe_PP3115.html

It says the MAXIMUM amount of disk space available was 280 Million bytes (280,000,000 bytes).

Even the most basic laptop nowadays comes with about 160Gb (160,000,000,000 bytes) of disk space (over 500 times as much), in a box the size of a cigarette packet.

And my camera has 8Gb (8,000,000,000) bytes of memory in a card the size of my thumbnail.

[VHG]

The other thing that has grown is how much computing power they can pack in a computer.

The early computers uses valves, which were bulky and unreliable.

Then transistors came in, then transistors on a chip.

In the 1980s there were probably 50,000 transistors on a chip (give or take).

In the 1990s there were probably 5 million.

Nowadays they are in the hundreds of millions. The CPU in your computer may have 200 to 500 million transistors on it.

Read on the interent that Intel have built a CPU with 2 BILLION transistors on it.

[Fitzer]

I started work as a computer operator in 1980 on an IBM 370/158 which had 8 MB of main memory (as opposed to the 4GB that I have in my MacBook Pro), it was known as a multiprocessor as it could run more than one programme at once. It had both paper tape and card readers for input, as well as the 3420 tape drives (also seen as the computer in the BBC's Hitch-hikers Guide series). Hard drives were the 3330 removable at 30MB for an object 14 inches in diameter, 8 inches deep and weighing about 10-15 lbs. Fixed storage was the 3350 for 50MB in a box about the size of a tumble drier, as opposed to the 500GB 2.5 inch drive in the Mac. We replaced the IBM with an Hitachi box which had it's own water cooled air con which blew one day and flooded the entire place, those were the days!

[scotman]

When I went to Uni our department had a computer of its own. It was an old second-hand Elliot of some description. Paper tape loading which you created on the old teletype machines. First load the compiler then the program.
You could open various cover panels and pull out the boards which had individual transistors etc on them.
At that time the Uni machine was something by Burroughs and it was punch card input. That was my first introduction to serious typing.
Happy days!

[Vagrant]

I started my career in computers in 1974 was as programmer on one of these, a Burroughs 2500: http://tinyurl.com/yh35wl7.
It had 40kilobytes of magnetic core memory and 1 megabyte of disk space.
The memory was about the size of 5 single wardrobes.
The disk was about the size of 3 washing machines, and needed a 3 phase mains supply. The disks inside were about 2 feet diameter.
The whole thing must have weighed several tons, needed a room 20 feet square, and needed several tons of air conditioning plant.
A typical modern laptop would have about 50,000 times as much ram and about 150,000 times as much disk.

[Vagrant]

The link above doesn't work - this does
http://tinyurl.com/ya47ezw