
New Chips Loaded With Dummy Parts - naish
http://spectrum.ieee.org/semiconductors/design/new-chips-loaded-with-dummy-parts/0
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silvio
This is an interesting case of the relationship between abundant and scarce
resources. It used to be that transistors were scarce, so using the silicon in
order to pack them well was the optimization goal. Nowadays, transistors
reached a point of zero cost, but yield and the process nodes to make them are
incredibly expensive, therefore, you get "wasted" silicon.

In programming, this is akin to programming in assembly, when no cycle can be
spared, versus programming in the highest available language, when the
programmer's attention and productivity is scarce.

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joezydeco
What about compilers that stick in NOPs to keep pipelines in sync?

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duskwuff
Less "to keep pipelines in sync" and more "to align jump targets to cache-
friendly boundaries". But yes.

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joezydeco
Yeah, didn't think about that one. Good one.

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altano
>Intel improved the resolution of its lithography with a technique called
dipole illumination, a process that splits light into two beams, sends them
through reduction lenses, and projects features from different angles.

That's so cool that someone had to figure out how to shrink LIGHT so that one
can watch cats doing cute things on YouTube.

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rwmj
This technique has been used in PCBs for many decades. You fill in unused
parts of the PCB layers with stripes, partly to improve the manufacturing
yield, and partly (in ground planes) to "debounce" the circuitry.

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wglb
Interesting. Kind of the junk DNA of chips.

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NathanKP
Not really. The dummy features have a practical purpose to help the silicon
deal with stress. Its similar to the ridges and lines that car manufacturers
are putting on the panels of new cars. The metal is so thin on these panels
that they have to put ridges to stop them from bending. The same thing has
happened with processors. We have reached a point where the chips are so small
that similar ridges have to incorporated to even out stress within the chip.

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bmelton
You might be dismissing the point too soon. To the lay-person, junk DNA looks
like as useless a feature as a ridge in a door panel, or dummy pathways on a
chip. To an expert auto-maker, the purpose of the panel ridges is obvious,
structural rigidity. To an expert chip-maker, the purpose of dummy pathway is
obvious. To Our Holy Creator Who Art in Heaven (or whomever you wish to credit
our creation), it is possible that our junk DNA has a very obvious purpose
that we have yet to divine.

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SwellJoe
Greg Bear's _Darwin's Radio_ is an interesting scifi take on the idea that
some junk DNA could be just one evolutionary step away from being activated.

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jacquesm
Darwins Radio was a great read but I don't find the idea of ready made
features for future use in our DNA very plausible.

He spins an amazing yarn around it though, and plenty of the social
consequences are very believable.

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gcb
Wooooosh ... sound over the head of a software guy reading this.

