yes old core 2 extreme is bottlenecking your graphics card...
you can try to overclock it a bit if you have decent motherboard and aftermarket heatsink...
but you should really consider an upgrade (buy haswell i5 chip with 1150 socket motherboard and 8gb of ddr3 memory)...
good deal ...
D3H is great motherboard for overclocking
and with 4670K + amd r9 290 you will be able to play every game on the market at maximum settings smoothly...