The heat issue is well covered by fuzzyhairfuzzyhair. To summarize the transmission delays, consider this: The time needed for an electrical signal to cross the motherboard is now more than one clock cycle of a modern CPU. So making faster CPUs isn't going to accomplish much.
A super-fast processor is really only beneficial in massive number-crunching processes, and then only if your code is carefully optimized to do it'sits work on-chip. If it frequently has to go elsewhere for data all that extra speed is wasted. In today's systems the majority of tasks can be run in parallel and large problems are split over multiple cores.
It sounds like your latex compile process would be improved by:
- Faster IO. Try a RAMdisk.
- Running different documents on different cores
- Not expecting a 200-page image-intensive job to be done in 2 seconds