To be honest I feel Intel's mobile processors are overpriced these days, as they're both more expensive and less powerful than desktop processors from 5 years ago. However, among Intel ones, there's a few I might posit as guidelines:
- I'd avoid the Core M ones. They use the least electric power, but are also the least powerful laptops, and are generally no less expensive than the Core i5 line. They're good if you need a super-thin, long-battery-life travel laptop, but not for Civ AI turn times, and the benefits don't matter as much if they're only used at home.
- The Core i3-6100H is a decent mid-low end one, with a list price of $225. At 2.7 GHz dual-core, it is considerably faster than the 1.8 GHz dual-core that Beyond Earth states as a minimum, and should suffice for Civ6 as well.
- The Core i5-6350HQ is likely the sweet spot for a quad-core, at a list price of $306 for a quad (2.3 GHz with boost), with better graphics than the i5. You wouldn't have to worry about Civ running well. The Core i5-6300HQ combines the quad-core with the i3's graphics - less shiny, but same AI turn times as the i5.
- The Core i7 line starts at $378 list price and is certainly in diminishing return category, not really worth it if you're trying to be cost-reasonable.
The list prices are just for the CPU, so any laptop with these will cost at least a couple hundred more if the quality is anywhere decent.
AMD's processors are an interesting alternative, particularly as their most recent ones ("Carrizo") have respectable battery life. While their peak per-core performance is lower, it tends to be less costly to get a quad-core, and the graphics tend to be a fair amount better for the price. Basically, anything in
this table with 4 cores would be worth considering. The ones farther down are up to 33% faster, but all are quad cores.
In the end it will depend somewhat on whether Civ6 uses a truly multi-threaded AI. If it does, the AMDs will likely wind up being the better deal from a combined CPU-GPU perspective. If it doesn't, the Intels likely will if you prefer large maps, and if you prefer small maps the AMDs will likely win anyway due to slightly better graphics. Not really sure how likely it is that Firaxis will go with a multi-threaded AI; I thought they might for Civ5 but they did not.
