how to determine which graphics card is superior to another?

[thevillain]

for example, from these two which is better

http://www.amazon.com/dp/B00FLMKN6I/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=31H4TK1CRRBT5&coliid=I2SPVGRZFEWT3S

or

http://www.amazon.com/dp/B00GP6JIEC/?tag=pcpapi-20

 

[BustaRhymes]

You could look up the benchmarks. The Model numbers also are mean't to give you an idea of how powerful they are. For AMD the R7 cards are low-midrange cards and the R9 are high-enthusiast. 280X is higher number than 270X so the 280X is more powerful.

 

[Alpha3031]

280X is better

For a general case

First, newer cards usually have better performance/price, otherwise the more expensive model is usually better

Second, Dual GPUs on one card are usually more expensive than the corresponding 2 GPUs on separate cards

Third, higher clock speeds mean faster card (on the same model), but you can usually do this after purchase

AMD cards are usually cheaper at the same performance levels, this is balanced by NVidia using higher quality, more features etc.

For a specific use, it is best to look at FPS on the specific thing