I am going to make animation what hardware i have to use

You can use any PC hardware they will just do it at different speeds. Which program are you using?

If you are planning to use it exclusively for animation and renderings,

1) Good i7 CPU
2) 32GB of ram if possible ( at least 16GB )
3) Good nVidia Quadro or ATI Firepro card
4) Monitor with 100% RGB gamut
5) Decent SSD with capacity of 256GB or above
6) Good HDDs with raid configurations