I guess you understood from the previous replies that you need a good GPU to mine anything at all.
thank you very much! you are awsome! What about network? is network speed another big matter?
No it's not a big deal at all. In fact, a 1mbps line will do just fine. The mining rig just uses the internet to submit shares to the mining pool which is nothing really just some numbers sent and received.
I mine Litecoin on a similar computer, but with a powerful video card. I even managed to earn some money on this. But now this power is not enough for mining.
You're totally wasting your time and wasting electricity for nothing. Thinking about mining any coin without a decent mining rig with new Nvidia or AMD gpu cards.
But even with modern high-end gpus, mining a coin on an algorithm that already has ASIC miners for them is wothless. These asics produce way way more hashpower than our cards. The only "profitable" way to mine litecoin for example is to buy antminer l3+ right now.