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HP Introduces Defect-Tolerant Nano Elements
versicherung writes "With the ever shrinking feature size in microelectronics it will soon be prohibitively expensive to manufacture defect-free nano elements. HP has come up with a new way to produce fault-tolerant microchips. Utilizing mathematical techniques borrowed from coding theory, HP will be able to produce those chips by using a cross-bar architecture and adding 50 percent more wires as an 'insurance policy,' to fabricate nano-electronic circuits with nearly perfect yields even though the probability of broken components will be high."
Wouldn't the cost be the same. Say 50% more wires= 50 % less errors, but you still spend 50% more on the wires there, so you would still break even because even though your yeild is 150% of the original, the chips will also be 50% more costly because there's 50% more wires in it.
Not all chips are CPU's. Besides for a CPU you don't want to waste a lot of transistors on redundancy. This is obviously made for minor chips that don't produce a shitload of heat and don't need to go any faster.
Actually its both, with more quantity, comes more fault tolerance, and with that comes better quality. When modern silicon has half a billion transistors you have to prepare for some of them to not work if you ever want to have a usable product.
There is truth in humor.
The increasing use of spare circuits could let product makers offer variable-performance, gracefully-degrading products. As the product degrades it would map out the bad circuits, but keep functioning. An overclocked GPU might be specced to have 16 vertex shaders, come from the factory with 18 working and then slowly lose them over time (but not drop below 16 during the warranty period). Used long enough, it might steadily lose vertex shaders until it can no longer function.
For example, I wish my ATA hard drives would let me access all of the space on the drive, including spare blocks tagged for remapping of bad blocks. A flexi-capacity drive would show higher-than spec capacity on first install and then gradually degrade. Standard practice of never using 100% of a available space would guarantee the availability of at least a few spare blocks. Current drive logic fails the drive once the spare blocks are used up, but a smarter drive would keep working by steadily shrinking the drive capacity. The OS might show this as a steadily-growing, locked "BAD_BLOCK" file. A well-used hard disk might last much longer, but shrink below rated capacity and still function adequately.
A dynamic version of this technology would be a real boon to over-clockers. Say you buy a heavily multi-cored CPU (guaranteed to have at least 32 of 40 fabricated cores functioning). It might come with 35 of the 40 fabricated cores working at design clock-speed. Over-clocking might knock out a few cores that were marginal but let the system's user optimize the speed of the cores vs. number of usable cores in realtime. A fully dynamic self-testing, self-healing system might automatically bring marginal cores back online once the clock-speed is dropped.
I realize that companies currently sell the same chip with different ratings by testing for speed or usable components (e.g. usable vertex shaders in a GPU), but what I want is different. Rather than use spares to guarantee some fixed spec performance (the current industry practice of leaving only a fixed set of available good components active on a chip), users could enjoy both more initial performance and longer life from products using a dynamic self-testing, self-healing system that uses all know-good components. Such systems would gracefully degrade as vertex shaders, disk blocks, RAM cells, or cores die or stop functioning at high speeds and temperatures.
Two wrongs don't make a right, but three lefts do.
Congratulations, you cobbled together a bunch of words into a nonsensical post, got your first post and even got modded "interesting" by a clueless mod. Kudos Slashdot.
If you want to know whether this sort of design is acceptable, ask whether CDs and DVDs are acceptable. They are founded in coding theory, and are designed to have many bad bits, and yet still contain perfect information.
Well, do you think internet protocol is inelegant? If you have to send information through a noisy channel where one in every 10^3 bits gets flipped, you need some mechanism for error correction or you simply can 't communicate.
Now we're not talking about communication channels here, but the analogy is the same. There are some factors we as engineers can't control (such as thermal noise, for example) and so we have to work around them. I won't get into the technological details of nano-fabrication right now, but suffice to say the problems are very difficult. And since these are nano-wires, extra area barely hurts you.
That's the key; nano-circuits are miniscule... like two or three orders of magnitude smaller than the transistors we can make right now. Extra wires are no problem.
If it really works, then it's not just useful "as long as defect rate is high". Think about it, current technology assumes that everything needs to be perfect, but if you can tolerate some defects, then you can be a lot more aggressive in the design. That means using a smaller features, lower voltage, higher clock rate, ...
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