It is suggested to replace i3 2 120 original (770 yuan)+Gigabyte H6 1(370 yuan), 1 100 Yuan, which is far superior to AMD64 1.
Chassis is not important. Please use domestic brands with caution, and use Taiwan Province or foreign brands, such as Delta and Antaike.
The configuration of the last Antec ECO400 (299 yuan) of your machine is stable and reliable, saving electricity. There is nothing wrong with the graphics card, which is more mainstream. What is memory 1666? 130 yuan weigang DDR3 1333 is enough.