No, it would be a waste of money.
BTS is large address aware, meaning that it can theoretically address up to 4 GB, though it really cant use all of that for some reason. I've never had BTS go above 2.5 GB on a huge map, but I've also never had a MAF error.
I read somewhere that a graphics card with low memory can cause MAFs in graphic intensive games, but I don't know how true that is, and I don't remember where I read it.
There is a four GB switch program that may help. Search the forums for MAF errors and you'll find it. Otherwise, you're stuck with playing smaller maps...