It's unlikely that MTW2 is optimized for the multicore processors currently in vogue. Or to exploit DX10 or 11. Plus you are playing a mod so all performance bets are off just for that if the unit sizes are expanded much. I haven't played Third Age on my current I5 rig but I did get lousy frame rates with multiple Mongol stacks on the field at the same time. Shogun2 runs great with 6000 men in combat but MTW2 becomes a slide show with that many.
And welcome to the Org!
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