Best increase would be by lowering the multi and increasing the fsb. Any increases should be done in small amounts. However, you would only see a noticeable increase in performance if you could continue to run the cpu/ram in sync. If you could get both up to 200 then you would see a decent increase in performance. The NF7 gives you a variety of ratio's so you could test the ram at 200 whilst keeping the cpu at 166 and vice versa. You don't necessarily need to increase the overall clock rating of the cpu to get an increase in performance. One thing you have to do is watch the temperatures though. Its one thing getting it stable but don't let it get too hot, which increasing the volts is bound to do.