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Colossus has been Rebuilt
Max Driver writes "In celebration of D-Day, "Colossus", one of the earliest electronic code-breaking machines, has been rebuilt after ten years of effort by computer conservationists. Colossus was used to break the Lorenz cipher. This story is being reported by the BBC. Remarkably, the use of parallel processing (five tape channels) and short gate delay time (1.2 microseconds) allows the Colossus to match the speed of a modern PC."
The code breakers in these small prefabricated huts probably shortened the war by two years and saved hundreds of thousands of lives. Surely us geeks can help save this site and remember their contribution? If you can't get there to volunteer, maybe use their online form and give them a small donation? Their website is going to be slashdotted at this rate, so how about slashdotting their intray with donations?
Yes but you have to remember that it was built to do one specific thing. When you design something for a single use, you get to make all sorts of assumptions which will allow you to optimize very very much. My DVD recorder is probably hundreds of times slower then my Athlong 64 system yet no matter what software I use it records video smoother with fewer frame drops. On the PC something happens like it becomes neccecary to flush the disk buffer and it will drop a frame, its hardly perceptable but sometimes you can detect it. PCs are so universal that you get to make few if any assumptions and that means more processing time. I imagine if you tried to write software for this thing to say transcode mp3 files to odd or something riddiculus like that your PC would finish months before this machine does.
Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
Don't talk utter rubbish. You should be modded down for being a crank.
This is custom hardware designed for the job. MHz and GHz don't come into it. If you don't believe me, consider why the processor on so many graphics cards is slower than the CPU in the machine, yet without it, the graphics would grind to a halt. A modern PC is a general tool - Colossus wasn't, and was specifically designed and built to break crypto as quickly as possible. Now, if you were to try and run Pong on it, fair enough, you'd find it incredibly slow... but that's not what it's there for. Colossus would however easily crack Enigma codes quicker than your over-clocked P4. And it probably doesn't have as many neon lights in it.
Funny thing about slashdot - people seem to think they know all about hardware because they know the difference between a MHz and a GHz.
If everyone did only what inspired them, alot of the unglamorous products and services we take for granted would not exist, and everyone's lives would be less for it (of course, I could do without my MTV, and the endless wasteland of product differentiation...)
Some people don't have any aspirations beyond drinking beer and fishing, and no vision beyond determining what is for dinner. That is fine. Everyone has a purpose in the grand scheme of things, or if they don't, one will be issued to them at some point out of necessity. Perhaps raising children is their life's world-changing work, while their job is just that - a job to put food on the table. I know this might be a shock to you, but life does not have to center around your occupation; your occupation can be on the periphery.
The really free, self actualized people are the ones living under the highway overpass in cardboard boxes. The rest of us do the best we can with what we have, and what necessity dictates.
Lodragan Draoidh
The more you explain it, the more I don't understand it. - Mark Twain
You'd still need to transfer data through the AGP bus. More data than currently is done, in fact.
Modern graphics cards assemble each frame from a collection of images, or textures, that are provided it. The GPU performs mathematical operations on these textures in order to orient them somewhere in the field of view.
If you performed all of the operations on the CPU, you'd not only be taking up instruction cycles, you'd have to transmit entire frames through the AGP bus. 1600x1200x24bytes works out to about 44Mb per frame. At 24 fps, that's about one gigabit per second. That's an awful low refresh rate. Let's raise it to 56Hz. Now we're at 2.33Gb/s, more than normal PCI. Let's go for a smooth 85Hz: Now we're at 3.54Gb/s. Let's look forwards to higher resolutions, say, 3200x2400@85Hz: 14.17Gb/s. More than the latest HyperTransport revision can handle. By this time, you've already crowded out hard drive and network access. Your sound might be in trouble too.
That's an awful lot of bandwidth. And don't forget the space on the CPU die, and cache pollution for other processes. And Memory latency, not to mention the fact that a lot of that memory could be used for other game data.
That's not to say there wouldn't be advantages. You could also conceivably perform physics calculations like collision detection and simple FEA.
All in all, though, it's more efficient to have a multiprocessor setup where specific tasks are run on specialized hardware.
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