Ram/ram slots not working

[tianfeng]

So one more problem with my Crosshair V board. I had to take the heatsink off of one of my corsair vengeance ram stick so it would fit under the nh-d14 cooler. I thought it was working fine but Yesterday i realized that windows is showing 3.96 usable of 8gb. My bios are also only showing 4gb of ram. I figure i messed up the stick but when I move it to another slot by it self it worked. the front 2 ram slots. one of which needs to be used for dual channel will not boot up when the ram is installed in them. When switched to the 3rd and 4th slots pc boots and shows 8gb of ram in a single channel set-up. After running memtest86 when the ram was in the 4th slot I did not receive errors. This leads me to conclude that there is a problem with the first 2 ram slots. Is there anything else I need to do before RMA'ing this board and having it replaced? This problem along with the sound loss while spdif optical out makes me think I have gotten a faulty board. I got it for NCIX and paid for the epress RMA so i should be ok. Swapping out my motherboards is so much hassel. Is there any user error here or am i just SOL?

[moocow]

Assuming you try pressing the RAM in hard enough and check the locks are in place, then you need to RMA the board. I don't ever recall seeing a BIOS setting that disable RAM slots. Also, try cleaning it first with compress air, may be some dirt got in the RAM slot.

[futures]

Try an electronic contact cleanser spray - on the sockets and on the traces. If you've never used one before, I suggest you try it on a cheap electronic device. They are suppose to be non conductive and quickly evaporate - don't even need to wipe them.. just wait 15 - 30 minutes.

Cheers