1GB DDR3 vs 512MB GDDR5

[YrralRellim]

I read thru the 20 Oct. 2012 "What's the difference between DDR3 memory and GDDR5 memory" and nearly all of that is way beyond my comprehension so I believe I am relatively a newbie on memory! (https://www.techspot.com/community/...-between-ddr3-memory-and-gddr5-memory.186408/). My question is probably simple for a memory expert but if I have a choice of buying one graphics card and hypothetically they sell for the same price - which card should be my choice --- 1GB DDR3 or 512MB GDDR5? Thank you.