4 ms·
> Does anyone know what we have now? I can't quote exact figures but to give a ballpark figure, we're talking about ~5 picojoules per bit at a distance of less
by exDM69 11y ago
> Does anyone know what we have now?
I can't quote exact figures but to give a ballpark figure, we're talking about ~5 picojoules per bit at a distance of less than 10 millimeters. This is on a modern (20 nm) SoC.
So we're talking about a pretty significant improvement in power consumption and communication distances. A modern chip running at 2-4 GHz requires several clock cycles for a bit to reach from one corner of the silicon to another. It's becoming a major hurdle to think about when designing chips.
- thecopy 11y agoDoes this imply that it will be possible to increase the clock-speed 5/1.3=3.8 times and still be able to cool the CPU with basic air-cooling?
- exDM69 11y agoNo, I don't think so. I don't think that light can be used to replace all (metal) conductors on a silicon chip, at least in the near term. However, this technology has the potential of bringing performance gains to on-chip memories such as L1 and L2 caches as well as software configurable scratch pad memory. Other possibilities that spring to mind are faster core-to-core communications as well as bundling more cores on a same die as the faster communication makes physically larger dies possible. disclaimer: I work in the semiconductor industry but this is not my area of expertise, my speculation is as good as anyone else's.
- typon 11y agoNo it doesn't. This does not affect clock frequency on a single CPU. This would improve bandwidth and latency in I/O with off chip circuitry such as memory or co-processors (like GPU).