Is it bad if my GPU usage is low while gaming?

Dylinian

Honorable
Mar 10, 2013
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When playing Tomb Raider on my 6670 getting about 35fps frames but my GPU usage is only about %65 , then in big areas my frames go down but my usage only goes up ten percent. is this a bad thing?
 

Dylinian

Honorable
Mar 10, 2013
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Full system specs,
Athlon x4 ii 640 3.2ghz
4gb ddr3 1333mhz
Radeon 6670 GDDR5 ( soon to be 7770 )
500w psu ( crappy one came with a cheap case , concerned my pc isn't getting the juice it needs )
1440x900
Win 8 64 bit
 

Dylinian

Honorable
Mar 10, 2013
80
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10,630
Getting 40 fps in tomb raider on high settings, then boom , 25 fps in big building zones such as shanty town. ( I do understand others have had these issues and that these areas are quite CPU intensive )