Thanks guys for your reply.
@cellard,
I already visited this website several times but I couldn't find my card listed.
@ranochigo,
Do you mean that cudaminer is not optimized for "Scrypt" mining? as I tried it with GUI-Miner for bitcoin and I got 25-70MH/s depending on the pool.
No, most nvidia GPU aren't that efficient if compared to the AMD GPUs. Bitcoins and litecoins are completely different, they have different algorithm to calculate for blocks, scrypt in general is harder to calculate than Bitcoin. Cudaminer is pretty much the best you can get for a nvidia gpu.