GIGABYTE RADEON HD 6670

Hi,

I have built a system with

CPU: I7 2600k
MOBO: P8Z68-V LX LGA 1155 Z68 ATX Intel Motherboard
memory: 8GB crossair 1600mhx
primay harddrive; OCZ Octane 128gb SSD

with all the configuration I am getting windows index of 7.6 and for graphics with 6.6

I was thinking for better graphics card and I bought

gigabyte radeon hd 6670 from Newegg on sale (47.00 after MIR).

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

with this new card I am getting windows index for graphics 6.8 (only 0.2 points increase).

Could you clarify is it really worth to buy this card? would it help me better than the INTEL HD3000??
Please let me knwo thanks in advace.