I Just built a new computer, It boots fine with one stick of memory, and I've made sure both sticks are good, from what I've read online I may need to set the speed, voltage and timing, myself in the BIOS. I'm using Samsung 2GB 2Rx8 PC3 10600u memory on a ASUS M4A87TD motherboard, and I'm having trouble finding what those settings should be (1.5v possibly?), also the there are many DRAM timing configuration options in my BIOS.. just a little in over my head here..
If your system fine , why do you want up. If you do fail set ram may you cannot boot or ram damage. I think for better let ram in the default system according to jedec and add size ram for better system.