I also have the i7 2600 (not K)
It is definitely no bottleneck.
Heck, the i7 930 the OP asked about is no bottleneck.
At this point with the graphics and processor you guys are talking about the only thing "bottlenecking" would be anything less than 4-6GB of RAM and a HDDGet at least 8GB RAM and an SSD (You'll be in great shape at that point)
i dont want to start a new thread, i want to ask the same for i7 2600 not K
and asus dcu II r9 280x top