I am a computer idiot, I would like to ask if there is any possibility of upgrading this configuration, and if I buy a used one how much is the right amount to pay out? Is it better to buy the whole m

I am a computer idiot, I would like to ask if there is any possibility of upgrading this configuration, and if I buy a used one how much is the right amount to pay out? Is it better to buy the whole machine or buy it alone? There is no possibility of upgrading ``If it is 2 hands ``with a monitor ``about 500 yuan ``

Without a monitor 300-400 yuan ``(mainly depends on the color ``)

I think that this configuration, unless it is a typing and copying department is useful ``

This configuration of the QQ stealing vegetables are stuck ``(because of the RAM is too small)

My home. 256M RAM 64M discrete video card machine steal vegetables are stuck ` later added a 256M RAM to get better ` still a little bit stuck.