I wouldn't think so. If the CPU was bottlenecking the 7970, it should still be at more then 35% util. Almost seems like a bug in the game/OS where its not usually all the modules that the BD has. Any chance you are restricting cores in windows?
I also noticed you said you were running win7 ultimate. I see this a lot, more so then ultimate should be used. I'm assuming you are using a hacked/downloaded copy. Might want to check for virus/rootkit on your OS. If your CPU is too busy running virus then you won't have the power for the games.
If the cpu not used over 80%, i doubt it bottle necked....
I think it's more like bad code/port of the GTA itself....
That is a common misconception, actually gta 4 is utilizing only 3 of his cores worth, he is never reaching 80% utilization but is still bottlenecking because of the FX's terrible single core performance.
It is a bad port on top of that.
The fact is he is leaving a lot of the performance of the 7970 on the cutting room floor because of his cpu.
I would love to get a new CPU but i dont feel that an i7 ivy bridge would be a worth while upgrade for only 10 frames more performance in games and considering it run hot when OC. would a i7-3930k be a good upgrade? or should i wait for the ivy bridge version?
Secondly how do i go about updating the game when its a steam version? shouldn't it be the latest version?