As Synthohol stated only a single kit is supported. You can try upping your system agent voltage .2v above default. And also Set the Dimm voltage to 1.55 or 1.6 since you have all your slots filled. But, i wouldn't go any higher than you need to get them stable,IF they will become stable.
You can test the memory with memtest to see if you possibly have a bad stick. Theere is a link on the left for the down load if you need it. Test each stick individually in the first slot. Let them run for three passes or until you get an error.
If they all pass, then i think the only thing you can do is RMA them in hopes you get a second kit to play nice with the first. Just be aware you chances of getting another on that works with the first are pretty slim.
Here is a 32 gig kit that should be compatible. It is a quad kit, but will still run fine in a dual channel MB as well. Let RamGuy give his final say though before you take that as gospel. :)