I like to write emulators as a hobby so I definitely feel your pain, but I'm not holding my breath for a significant frequency boost in the near future. A 4GHz CPU means that every cycle light itself only moves about 7.5cm in a vacuum. If you have a fiber optic cable running at 10GHz at any given time you effectively have one bit "stored" in the fiber every 3cm or so.It's frankly insane that we manage to have such technology massed produced and in everybody's pocket nowadays. My "cheap" android phone's CPU runs at 2.2GHz, 2.2 billion cycles per second.

We can probably still increase the frequencies a bit but we definitely seem pretty close to some fundamental limit in our current understanding of physics. The frequency doublings every other year we experienced until the early 2000's are long gone I'm afraid, and they might never come back until we manage to make a breakthrough discovery in fundamental physics.

I think it’s more of a power dissipation issue. The amount of charge, thus current, you are moving in and out of the gate capacitance is proportional to clock frequency. Sine power is I^2*R, then it is proportional to f^2.

Smaller transistors reduce the I, but R goes up with smaller interconnects. The RC time constant also adds delay, probably more so than length.

That being said, 3D stacking won’t help with heat, and dielets won’t help with delay. I rather have 4 cores at 10 GHz than 64 cores at 3 GHz.

You can probably rewrite the codebase to utilize n threads before anyone releases an 8, 12, 36ghz CPU.

It’s electromagnetic simulation, specifically finite element. You can parallelize some of the math, but mostly not. You can break the structure into smaller sub-domains, but that has issues too. Not much gain beyond 2-4 cores.

Not my area of expertise, but I was under the impression that finite element analysis, like other sparse algebra problems, are reasonably well suited for GPUs, which are much more parallel than 2 or 3 cores. Have you looked into that?

The time domain codes work well with GPUs and multiple cores, but the frequency domain ones don’t. I don’t know enough of what’s going on under the hood, but it’s like that for all of them.

I've worked with applied math PDE people and they use supercomputers to full effect. Granted it's a real pain and your cross connect bandwidth matters (hence supercomputer), but you can scale up pretty well.

I thought FE was mostly memory bandwidth bound?

Everyone wants faster CPU cores. Can you imagine how much simpler it would be to just program a 40GHz processor instead of writing a program that supports 10 4Ghz processor cores?