Newbie help

So im stuck in the dilema of gettin crucial 256 pc2700 for $70 or crucial 256 pc2100 for $35. Im buildin a system for the first time and probably WONT overclock since I would be screwed if something died because of ocing. So based on the fact that im probably not gonna oc anytime soon would the cost between pc2700 and pc2100 be worth it for the performance i would get with out oc'ing. I plan to get an MSI Ultra ARU if that makes a difference. THanks in advance

No the performance increase isn't worth $35.
You could put the $35 into getting a faster cpu that would make more of a difference if you are not going to overclock.

If you get a northwood cpu and don't overclock some you are crazy