I want to buy new computer, but I have low budget. I have to consider about used computer HP Compaq Elite 8300 SFF with Intel Core i5 3470 or assemble my own with AMD Athlon x4. Which processor is better? And if I want to use Radeon RX 460, which processor will be better to work with? Also, I have read about locked BIOSes in HP computers that not allow to add new hardware. Will new graphics be usable in it? Has the motherboard some unlocked BIOSes that allow new hardware?