I'm actually a really big fan of Moo0 system monitor, it's been my go to replacement for former gadgets on windows 7 (since they're extremely bad for security.) I've got several things monitored here's an image of what mine looks like here.
lot of suggestions here. I'm no pro, but use Mooo system monitor. If you are bottlenecking or your CPU is failing or over heating, it will tell you. One thing I love about that monitor is it tells you exactly what is bottlenecking.
I had a problem similar to yours with BFBC2 a few years ago, ended up being a fan of all things using too much power. Mooo told me the fan was sucking up more power but not spinning, for whatever reason, it was making my graphics card stroke off. Unplugged the fan, never had an issue after that (as odd as that sounds.)
http://www.moo0.com/?top=http://www.moo0.com/software/SystemMonitor/
Try it if you haven't, won't hurt.
I also use Moo System Monitor so I can see when a process is hogging something and you can clearly see when an AV is actively scanning your game, EVEN THOUGH YOU TOLD IT NOT TO!
Use this and run a game in a window next to it. If you see any of the graphs going dangerously high, that component is the bottleneck.
I use moo0 system monitor, have been for a long time.
It will provide you with many stats on your system, including CPU and GPU temps/load and the process that's currently bottle-necking your system. You can right click and go to a setting that allows you to show/hide multiple stats.
I keep it up on my second monitor all the time and monitor my system consistently.
In fact, just yesterday I was playing the Division and noticed weird huge artifacts all over - looked at the tool and saw my CPU temp at 90C + .. I shut down, blew out all the dust and am back to normal temps.
http://www.moo0.com/software/SystemMonitor/
They have a couple other neat tools too.
It's not the prettiest looking tool but Mooo0 System Monitor will give you details on what's hogging up all the disk read/writes ect so you can narrow it down.
http://www.moo0.com/?top=http://www.moo0.com/software/SystemMonitor/
Got a second screen? Grab this lil app its really handy to figure out where bottlenecks are and what your PC is doing. I would also go ahead and grab this and turn off parking then rerun your lil test and see whats up.
I have a 7870 with a 8350 OC'd to 4.5Ghz 7870 vs R9 270 With my system I am currently limited mostly by what the GPU can deliver. You might give this neat little program a shot - MooO It shows in real time what is your bottleneck, GPU, CPU, Disk, Etc.
Games are a fickle beast, some are GPU heavy some are CPU heavy. The GPU requirements are tweakable with settings but you can't really adjust how demanding any application is on your CPU. That being said I really don't see your combination of GPU-CPU having any real major limiting factors on each other, you have a nice 4 core OC'd CPU and a good GPU.
You're showing 12gb as the video card is mapped into the top 4gb of address space.
Might be worthwhile installing the Moo0 system monitor, leaving it 'always on top' and keeping an eye on the bottlenecks.