Found the CPU I had back in 2007. Also found the original invoice of the PC it was in. Unfortunately, the mobo and case (w/ a crappy PSU) are no longer existent,
14700円 i5 12400f PCパーツ afriendinme.org
ヤフオク! - Intel インテル Core i3-2120 3.30GHz FCLGA1155 ①