A G210 requires very little power, but 10A on the 12V rail isn't enough for anything these days. Your CPU, GPU, and motors all run off of the 12V rail. A G210 needs about 30W(~2.5A), if you have a 65W CPU thats another 5.5A. If you have two hard drives in there you are pretty well out of current on your 12V rail.