Hi Al Dee,
Welcome to the forum,
I appreciate if you give us more infos about your configuration system.
(PSU, Graphics Cards, CPU, HeatSinkFan... etc...)
Please give us a official brand's web link and exact model of your hardware.
Do not forgot a version and type of Windows... (by exemple : Windows 64bit x64 Professionnal)
Otherwise, check the QVL Quick Vendor List about compatible memory with your motherboard.
EDIT02 : http://download.gigabyte.eu/FileList/Memory/motherboard_memory_ga-ep35c-ds3r_2.1.pdf
Or in the official web site of memory's Brands.... before make your choice.
EDIT01: I check your motherboard here...
http://www.gigabyte.com/products/product-page.aspx?pid=2740#spThe maximum of Ram is 8Gb.
If you want more 8-16Gb, I suggest you tried it in the Shop.
It is more safe to do so front of the seller at the counter.
Who knows, maybe it will work.
With timing above .. Instead of 4-4-4-12 try 5-5-5-18 for example.
it helps to ensure that the ram is recognized by the motherboard.
This is just an example.
It does not apply to your situation.
EDIT03: Use CPU-Z, SPD and memory tab. For find a timing.
EDIT04: If you have the money buying DDR3 1600 or 1333.
But I am not sure if the DDR3 is necessary... unless you want to use it on another motherboard in need of DDR3.
No need to purchase faster.
It does not appear in practice.
And you have a possibility to overclocked a RAM. With a modification in timings. So... reduce to less than 5.5.5.18 by exemple.
Be care... this is just a exemple. Find a timing with CPU-Z.
Gloup_Gloup