I need a good Gaming PC. Fair enough re Bangladesh stores! Memory isn't the most important aspect of a graphics card, but it definitely affects performance (particularly with extra visual effects). This is why I highly recommend you get the GTX 970 as your video card (brand is largely irrelevant, as long as you go with a major manufacturer like Gigabyte, MSI, ASUS etc.), as it comes with 4GB, support for the newest technology and is very reasonably priced for the performance - so much so that you may be able to afford two which would set you up to run any game on decent settings for the next 2-3 years!