hey there. I'm new to pc building and put together a new rig yesterday as a budget gaming computer. I'm running an Amd fx 8 core so was limited in the motherboard I could choose. I ended up getting one of the low end that support am3+ http://www.asrock.com/mb/AMD/960GMU3S3%20FX/. This motherboard supports dual channel memory but I can't seem to use my memory sticks. I plug in 2 identical 1333 hertz ddr3 sticks which are recognised in my computer properties but when I open task manager only 2 gb is being utilised. So I took out one card and used only one slot and it worked fine. I used the same card in the other slot and that slot didn't work, I fact my computer didn't even boot up. Sorry if this sounds vague, let me know if there's any info I missed.