Do I have a CPU Bottleneck?

I have an entry level system im running, learning as much as i can so i can make an educated upgrade. So my question is, how to tell if i have a cpu bottleneck on my graphics card?

Specs: Core i3 530 @ 2.93Ghz, H57 Generic Motherboard, 6Gb ram 1333mhz, Asus Radeon HD 6670

Monitor: 1600x900 Resolution

I recently added the graphics card for online games, it was a fantastic improvement, but now im getting into PC gaming and i need more power. So is there a way to test if i have a cpu bottleneck? I was just playing Fallout: New Vegas, on High settings, I have large drops in FPS from 60 to 30 often, and my GPU usage is usually 60-90%. I can not overclock my cpu, the bios is locked. The cpu usage is usually around 70%, with spikes to 100%. Any help would be appreciated!

I wasnt sure if this was the correct forum either.

your system is pretty even, except your low on ram.... the system as a whole is just a bottleneck.... try upping the FSB to OC your cpu, if you have good cooling (i.e. not stock)

I can not overclock, my bios is locked.

well, your system is slow....

except maybe you graphics card

How is he low on ram? Lol, I have 8GB and don't even use all of it.

This is just a very entry level build. If you want to upgrade, I'd just say you should save up some money and buy a new build when you can. You can always add a beefier graphics card, which will definitely improve your gaming experience, but you're probably not going to see its full potential until you upgrade your CPU.

Try an I5 and get 8gb of RAM at 1600 mhz, I've used the 6670 in several builds and it will usually play games on medium and high at stable 45-60 fps, always turn shadows all the way down/off, the 6670 simple doesnt have the capacity to run most triple A games like Crysis 2 or Battlefield with high quality shadows. Keep in mind that most high end games these days are multithreaded and optimized for quad core processors, a good I5 should definetely help. You can stick with 6gb of RAM as long as you close all your other programs before you run a high end game. When in doubt check a games "recommended" specs to get a ballpark idea of how much RAM you're gonna need. If your frames are consistently unstable it could be anything, if you get low framerate spikes when physics kick in on a game that doesnt use the havok physics engine, you might want to replace your CPU first. Keep in mind that games that use the PhysX engine will consistently run at low framerates when when physX is enabled, as Radeon cards do not contain the PhysX library, and all PhysX calculations will be done on a single core of your CPU, granted most games with PhysX offer the option to disable it, or offer a "low" setting. Good luck with your build. 

Cheers.

Thanks for the input, i have dug around some more and i do believe that i have a cpu bottleneck. For example, i just installed skyrim, and i was at 30fps, with 70% gpu usage, which should indicate a bottleneck. This is because the cpu renders the "surfaces" and the gpu renders the "textures", so if the cpu is not rendering the "surfaces" fast enough, the graphics card will not be under full load. Unless you are over 60fps with verticle sync enabled this can happen but is not a bottleneck. Can anyone confirm this? I do have a planned rig for later this year or Xmas, i posted it in the PC building section, and i may update it if the parts change.