DDR3 today, time travel tomorrow

Apr 16, 2007 14:47 GMT  ·  By

For a couple of decades, the memory modules have kept the same basic concept, with improvements being done to the mechanical part, how electrons circulate and so on. But, basically, the principle remained the same, and people were pretty happy with how things were going. Of course, when I say "people", I'm not referring to Intel[ADMARk=1]; oh no, they are the ones that seem to think progress must take place at any cost, of they lose money. Such is the case with their processors, always trying to keep up with Moore's Law, always trying to outdo themselves, these guys are in a desperate need of a break.

But things aren't over if Intel doesn't have the last word, and this word is one to pay attention to, because their plan is to change, yet another, computer component. This time it's the memory modules, seeing how DRAM modules, apparently (I didn't know), have reached the point where they are called obsolete. That is why Intel wants to give a demonstration of the next generation memory modules based on PRAM (phase-change RAM) technology. If you think of phase-change cooling, it isn't quite the same with PRAM, although it has to do with heat and electrical current.

PRAM uses the chalcogenide glass, an element that can switch between to physical states, crystalline and amorphous under the application of heat generated by an electrical current. The memory is non-volatile, and doesn't lose its information once electrical current has stopped flowing. The two states this element can be placed in have different resistance states; the amorphic state has a high resistance, and it is used to represent a binary 0; the crystalline state has a low resistance and represents binary 1.

Justin Rattner, Chief Technology Officer at Intel Corp., said: "We're thinking phase change is looking promising and we're going to go into production with that part in the second half of the year. It's not clear there's actually a wear out mechanism because your just moving this material, chalcogenide, between phase states. Inherently, that's not a destructive process. Ultimately we have to answer the question, is phase-change memory a replacement for DRAM? It seems to have the performance characteristics. Is it a new level in the hierarchy? Or will DRAM move into more of a new level of the cache hierarchy and phase change will actually be the main memory as we think of it today?"

The properties of chalcogenide glasses were first explored in the 1960s, soon to be looked upon by Gordon Moore, co-founder of Intel and responsible for Moore's Law, in September 1970, when he published an article concerning the matter in an issue of Electronics Magazine. Here we are now, decades later, going back to the original ideas, but looking at things from another alternative, back then, the prices were too high for this solution to be marketed and recent improvements have made it possible to manufacture this at a large scale. Other benefits of this technology include a virtually unlimited number of read/write cycles, unlike flash cells in, of course, flash-based devices which degrade from each burst of voltage and have a limited read/write cycle of 10.000 to 100.000 cycles.