What needs upgrading if I get launcher crashes when more than 30 people are on game?

[trademe900]

Ok guys so still can't play the channel map with more than 30 guys. Really want to be able to regardless of graphics settings.

I run the game with amd x2 260 and radeon 6670. I run on low settings and it is ok but crashes when there are more than 30 guys on the server.

I don't know how cpu intensive the game is and I am wondering if I can get by with a significant performance upgrade with a gtx560ti. I have no wish to play the game on maximum settings and am simply looking to eliminate the crashes with high player numbers and get a significant performance increase when on someone's tail!

What results do you predict with this change, given the cpu? Will it solve the issue?

Many thanks!