[Beowulf] Is there really a need for Exascale?

[Lux, Jim (337C)]

On 11/29/12 10:24 PM, "Mark Hahn" <hahn at mcmaster.ca> wrote:

>
>samsung has been producing stacked chips for quite a while -
>back to at least the a5 generation, probably before that
>(stacked dram, stacked flash too I think.)
>
>> The interesting part about forthcoming real (TSV) stacking
>> that you can mix hybrid memories, whether SRAM, MRAM, DRAM, flash,
>> as you don't have to be process compatible as with true embedded
>> memory (though MRAM might well be process compatible with CPUs).
>
>stacking is great, but not that much different from MCMs, is it?
>

There's also the techniques from places like 3dplus, which basically take
off the shelf parts and stack them after machining the packages a bit and
sticking what amounts to a tiny PCB on each side with the interconnects.

But...

Any time you go from "die" to "outside world" the assumption is that
you're going to be transforming from some internal logic level and
impedance to something moderately standard in the outside world (e.g.
LVDS, 3.3VTLL, etc.)  that's slow and power costly.

Even if you go die to die (as in a MCM or thick film hybrid) you're still
faced with this issue.




>