Gigabyte GA-H55N-USB3 Owners please help?

[Spooter]

I have also posted this message here but this possibly a better place and better title.

Just put together my new build and I have a strange memory issue.

System Specs

i7 860
Gigabyte H55N-USB3
Corsair Value 2GB DDR3 PC3-10666C9 1333MHz
Corsair Value 4GB DDR3 PC3-10666C9 1333MHz

The problem is Windows shows 6.00GB installed but only 3.96 GB useable. I am running Windows 7 64bit and the ram shows as 6GB useable in my AMD system. The ram also tests as fine.

I have tried forcing it to use 6GB of ram using MSCONFIG. I also have no onboard GPU so thats not the issue.

Its single channel ram but it should all be usable.

Could I have a faulty memory controller in the i7 860 I bought from MM?

If I put both sticks of ram in the PC it will boot and the maximum amount shows as installed but only the memory from one dimm is usable. If I only put the ram in the second dimm the PC wont boot. The ram tests fine in another PC. If I put just one module in the dimm nearest the CPU the PC boot but only a small amount of ram is usable by the system. For example right now its showing as 4GB installed (1.86MB) usable.

I guess the problem is quite similar to this.

Any ideas?

 

[Spooter]

Think I have sorted it..

Reset cmos and PC booted with ram showing as dual in CPUZ and all 6GB usable.

Strange!

Hopefully thats the end of that.

Anyone got any recommended overclock settings for this board with the i7 860.

 

[Spooter]

I have the Lian Li PC-Q08B USB3.0 case but still only running the stock cooler. I want to change the cooler for something better but not sure what yet either as there isnt much room...