Yeah looks like dimm2 slot is bad. Micro is like laptop you can install single ram in either slot and it should work.
Hi all, I wonder if you have seen this, or maybe you can suggest something: I have a Dell Optiplex 3070 micro with Intel T9100 processor and 8GB of RAM. I was looking to upgrade the memory. The memory that is now in it is one stick of Hynix HMA81GS6JJR8N-VK So I bought an identical stick and added it to the system. Unfortunately the PC doesn't boot and power button blinks amber 2 and 7 times. As per service manual the memory is the problem. I then replaced the original RAM stick with the recently bought one and it works. Basically both memory sticks work fine by themselves but not together. Which obviously defeats the reason why I bought the second stick. Specifications for the 3070 micro mention that there can be 2 sticks (2sticks of 8Gb each) so I am at a loss. Any suggestions would be appreciated.  
Add memory to an Optiplex 3070