I bought a Dell optiplex awhile back for $200 cash, I took out 4gb Ram out of it, leaving 4gb, took out the m.2 nvme ssd, replaced the 2tb hard drive with a 160gb hard drive and replaced the i5-6400 with a pentium g4400 and now I’m using the i5-6400 here after I resold the Dell optiplex for $200 after all the changes.
This motherboard was bought refurbished from Newegg when it was on sale for $19.99.
The 8gb stick of ram was taken out of an acer predator prebuilt gaming build and resold for more than I bought it for after ripping/swapping some things so I pretty much got the ram for free.
Hard drive was taken out of another system that came with 4 of these in raid 0, I took all 4 out and swapped it with a 500gb hard drive and sold it for more than I paid so pretty much got these for free.
GTX 660 was taken out of the same system as the hard drive, was swapped with a GTX 550ti.
Power supply was bought from amazon for $21.99, these are often sold at around this price range.
I found this case on Newegg, it seems to be a new model, was on sale for $39.99 with a $10 mail in rebate, nice cheap case with tempered glass.