When Installing your Operating System (OS), you need only use 1 dimm and start off by placing it in slot #2. After you get the OS installed, then add the other 2 dimms in slots 4 & 6. Start computer up and go into Bios', then to where you can change your memory timings or leave at auto. Once that is done boot into Windows and then shutdown computer if it boots with all 3 dimms (6gb) and then add the other 3 dimms in 1, 3, & 5 slots. That should solve your problem.
I'm not overclocking, no. When it first happened I was quite worried as I had only just put the system together and thought I may have fried something inadvertedly. However, after swapping the modules around I finally found out that it was the 3rd white DIMM slot that was causing the problem.
With 4GB RAM in the system I did try and use Gigabytes 'EasyTune6' software to overclock it, but the machine then doesn't POST if I attempt to overclock.
I have reset the CMOS and set the BIOS back to default but, alas, no luck!
I dont know if this limitation still apply, but I7 have kinde of screwed memory controler.
It doesnt work with tripplechanel activated and frequence over 1066 or 1333 (not sure which one) even if cpu is marked as 1600+.
If you cannot make it work with memory modules in slots 1.2.3 or 4,5,6 or 1,2,3,4,5,6 (only in this case cpu should use triple chanel mode i think).
Also try run memory on lower frequency if this make it work.
Other possibility is that your memory brand just dont like your mobo. (i hade similar issue with ADATA on asus board before, corsair worked fine).
Btw this is reason why i decided to skip I7 generation.
I'm going to re-post this (again): when the i7s approached release, I warned, long and loud, that this is not a good place for people with little or no systems experience to be. This is a completely new chip mask, with a completely new northbridge, a completely new memory technology ('direct connect three channel'), which requires completely new boards, with completely new BIOS! There were bound to be problems, and some serious! You should expect weekly BIOS upgrades, and scads of difficulties - it's, essentially, a huge 'public beta' project... If you have little depth of experience, and no knowledge of troubleshooting (hardware especially), nor have a serious reason to invest a lot of time in an untried platform - this is a really bad choice. If you expect building a computer to be like plugging in a toaster; if you're the sort of person who didn't do well in math or science classes (or just completely avoided them); ditto!
Everyone seems to think they've 'gotta have' the latest and greatest goodies that appear on the market - but a comprehensive set of untried technologies like this requires serious: effort, understanding, and, most of all - time! Most everyone I see here with X58 based problems would most likely have been infinitely better served to have stuck with a Q9550; I liken this situation to deliberately shooting yourself in the foot - and then complaining because you've got to change the bandage twice a week!
That said, the first point regarding these boards is the i7 setups show negligible subjectively noticeable gains from the currently available memory speeds: http://www.tomshardware.com/reviews/memory-scaling-i7,2...
so you needn't obsess about getting that last MHz that your memory is rated for... Slow 'em down to 1333, and see if they work.