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Comment by gaius | Hacker News Reader

And more transistors doesn't mean more performance. Why do you think modern CPUs have 6 or 8 cores on? Because we can fit more transistors on a die but CANNOT make individual cores go any faster.

You can massively parallelize rendering a movie in advance because you can do each frame on its own CPU. Rendering in real-time is much less easy to extract this kind of parallelism from, particularly if you have hard real time constraints.

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I thought the problem with faster as you go smaller is that smaller pipes leak higher pressure water (electron tunneling), which is why we have divided the pressure into a larger number of small pipes (multi-core).

If we can make higher pressure capable small pipes we could run then all faster. I bet there's billions being invested in solving this problem, but that doesn't mean it's solvable.

Modern CPU cores are faster than CPU cores from before the "multicore" era. I think we're figuring out how to make CPU cores faster _and_ pack many of them into the same space.

One of the main limitations is actually power, as increasing the frequency increases the power draw. All that power turns into heat, which has to be dissipated. Modern processors already shut off inactive cores and change the frequency of the active cores on the fly depending on the workload to reduce the power draw [1], so it's easier to add performance by adding cores. The problem is that software hasn't quite caught up to take advantage of the added cores.

[1] http://en.wikipedia.org/wiki/CPU_power_dissipation

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