Originally posted by Hobo Misanthropus:

Game is CPU heavy because of all the drawcalls. Even if your CPU doesn't see
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Cache, kicking things out of L3 into system memory.

or as i prefer to explain it " a chain is as strong as its Weakest link" then it breaks or in this case slows throughput down.
But since its not a chain it doesnt break it just slows down till we eventually turn everything down to minimum, and then labouriously turn them up one by one to see which causes the most pain. till we work it out from frustration :-) GL @Xanthia_D