So I'm buying this graphic card with 4GB. There are more versions of this card that have some things a little different but at the same price. Can you tell me if it's better to buy XFX Video Card AMD Radeon RX 460 GDDR5 1220MHz/7000MHz, PCI-E 3.0 x16 that needs a pin connection or GIGABYTE Radeon RX 460 WINDFORCE OC 4GB 1212MHz/7000MHz PCI-E 3.0 x8 that doesn't need that connection...is there a big difference? do you need better PSU if you use with pin connection? and is there a big difference between 8x and 16x PCI-E? My motherboard will have 16x