i thought radeon hd 7000+ is a good gpu.
It doesn't work like that.
7340 is horsestuff compared to a card like 5770.
The first number >7<340 represents the generation, this is the 7th. The second number 7>3<40 represents the series of the high/low end generation, higher the better, 3 is horsecrap. The last 2 numbers 73>40< represent the power of the GPU in that generation and series, 40 is terrible, 90 is the max. Basically the higher the last 3 numbers are the better. See why a HD 5770 is better than a HD 7340?
Same goes for nVidia cards. If I got the number order right.