help upgrading

Need to Upgrade but only 1 thing for now ....
there is my setup: intel dual core2 E6600 2,4 overclocked to 3,0 ghz, 5 ghz ram and a Geforce 9800 GTX+. Am running 5 wow instance on vista 64 now what will be the best to upgrade in order to run wow a bit better or at least with less lag in big town ? someone told me to upgrade the graf card to a GTX 260.

Looks like you need a quad core processor and 8gb of ram

CPU and RAM will bottleneck you before a 9800GTX will.

oki but I can change only one part right now ... :( should I go for ram or cpu ? also have only 250$ left ...

For wow, I'd go with the ram, to 8 GB, before upgrading the processor.
You've already got it stable at 3.0 ghz.