I have 2 voodoo2`s sli running @100mhz with proper cooling with the fastvoodoo 3,5 and a duron 1000mhz. When i look at the minimum requirements for medal of honor I could easely play, but in reality is is painfully slow i tested with several settings and resolution and came to the conclusion that the cpu had to do most of the work cause at 800x600 is was like it was at 640x480. note that I installed the wickedGL drivers.
Yes, you could get a better fps value by a cpu with a higher clock: in fact minimum requirements for medal of honor are very rough. Try use light settings for game audio and read this page for hardware optimization.