How to understand Graphic Card Model Numbers?

Both nVidia and ATi/AMD cards mention both the Generation and the target performance segments in their model number. Nvidia uses 3 digits, while AMD uses 4 digits currently.

For nVidia
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First number is generation, last 2 numbers give performance segment.

Eg, Geforce 610 = 6th Generation, 10 = Lowest performance card in this generation.
Geforce 630 = 6th Gen, 30 = Low Medium performance
Geforce 650 = 6th Gen, 50 =Upper Medium performance
Geforce 660 = 6th gen, 60 = High performance, and similarly
690 = Extremely high end card of 6th generation.



Also note that even last 2 generations high end cards will absoluely DESTROY new generations low end cards. Eg, a Geforce 480 will kill a Geforce 610 :)

For ATi/AMD Radeon
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First number is generation, last 3 numbers give performance segment.

Eg- HD 7990, 7th gen, 990 means Extremely high end
HD 7870, 7th gen ,870 means high end
HD 7790, 7th gen, 790 is upper-medium performance
HD 6670, 6th gen, 670 is lower-medium perf
and HD 6450, 6th gen, 450 is the slowest card of this generation.