Hi,
These 2 cards are so close in specifications that I am not sure you would notice much of a difference. I found that the 565v is a renamed Radeon HD 4670 mobility chip. Its clock speed is 675mhz, has 320 stream processors, and the ram runs at 800mhz. The radeon 5165 is a renamed radeon 4650 mobility chip. It runs at 600mhz, has 320 stream processors, and the ram runs at 900mhz. I think the one you purchased, the 565v would give slightly better performance due to the enhanced clockspeed of the gpu though.