When I first saw the die of Intel's Silverthorne (now part of the Atom family), my initial reaction was: "It's the same shape as an old-style DRAM. I wonder why that is". However, that's not the curious thing about Silverthorne, once I worked out – with the help of the paper presented at the International Solid-State Circuits Conference (ISSCC) – that the shape is pretty much governed by the memory bus logic.
The curious thing about Silverthorne is that it is just a processor – in a market where everything it will compete with will be a system-on-chip (SoC). OK, SoC is a bit of a misnomer in the context of a portable computer as you still need a stack of chips around the main one to make anything usable. The iPhone, for example, has them stacked and squeezed together to get everything it needs into a phone-sized package. However, Intel is looking at markets where devices such as Texas Instruments' Omap rule.
It is doubly curious when you consider Silverthorne's die size: 25mm2 is tiny. It is a little less than a quarter the size of the dual-processor Penryn, which clocks in at 107mm2. For a desktop Intel processor, the Penryn is surprisingly small. Intel has been known to go double that size for the first iteration of a processor.
