As a present I got the Asus Geforce 210. I know that it is a very cheap graphics card, but is it possible to use it for cycles rendering?
I have Blender 2.75a with support enabled (automatically) for Geforce 210. To check if itsn't a mistake, I enabled and disabled before rendering a scene. Yes, it works with your CUDA, NVIDIA GeForce 210. However, the latest RC version 2.76 don't detected my card (yet). Check if your NVIDIA drivers are updated.
Your card is no longer supported supported starting with blender 2.67. Quote from the manual:
NVIDIA CUDA is supported for GPU rendering with NVIDIA graphics cards. We support graphics cards starting from GTX 4xx (computing capability 2.0).
And even if you made it work, (See this post) that card has only 16 cuda cores. Rendering on CPU is going much faster...