There's no way 4x1GB is better (faster, update'able, etc) than 2x2GB, you can 'hoe' all you want
😉
Gigabyte GA-970A-D3 -
http://www.gigabyte.com/products/product-page.aspx?pid=3908#sp
4 x 1.5V DDR3 DIMM sockets supporting up to 32 GB of system memory **
Dual channel memory architecture
Support for DDR3 2000(O.C.)/1866/1600/1333/1066 MHz memory modules
** First, >4GB you need a 64-bit OS.
IMO 'today' only get 4GB/stick density kits or 2x4GB. RAM is very cheap and it's a no brainer for 2x4GB or 4x4GB sets. Further, if you have a non-FX then for ease get DDR3-1333 otherwise for FX CPU's DDR3-1866. I could see 1GB/stick and 2GB/stick debates a year or longer ago but not today.