Do these benchmarks seem right?

Hello all,

i recently completed a new gaming rig including the following:

phenom II x4 965 OC'd to 3.8 ghz (voltage set at 1.38)
cooler master x6 elite cpu fan
asus 990fx sabertooth mobo
evga gtx 670 ftw
2x4 gb corsair vengence lp @ 1600mhz
thermaltake chaser mk-i case w/ 4x200mm fans and 1x 120mm fan

I have run benchmarks using furmark and unigine heaven dx 11 and scores are:

Furmark: score was 3793 @1080p w/ no AA, fps stayed around 40-41

Heaven dx11:
fps: 54.9
score:1384
min fps:20
max fps: 63.9
resolution: 1080p
AA: 4x
shaders: medium
textures: high
Vsync: on
filter: trilinear
Anisotropy: 4x
occlusion: enabled
refraction: enabled
volumetric: enabled
tessallation: normal

nvidia control panel set to use 3d application settings

My experience is limited. These scores don't necessarily seem bad to me, but I was expecting more from a $400 video card. Does this seem correct, or might there be something im missing thats holding my system back?