Hey I about to buy a Sapphire Radeon R9 270X Dual-X OC 4GB but i was wondering if 4gb is to much for my mother board because ive only got a 2gb gpu at the moment. my motherboard is a : GA-78LMT-USB3 (rev. 4.1) link : http://www.gigabyte.com/products/product-page.aspx?pid=4305#sp