I have my very first CPU, I'm looking at it right now, it's in a plastic bag hanging from a cord strung catty-corner across my bedroom. Um, just removed it from its bag (first time since probably around 1994). Says:
Intel
i486 DX
A80486DX-33
SX419
INTEL 1989
I upgraded it with IIRC a year or two later with an AMD CPU, a 486-DX66 I got at a computer show. The computer itself was used and put together by an electrical engineer who (this was 1993) had decided to get rid of the desktop and go forward using a laptop, a pretty novel idea at that time. I used to call him from time to time and pump him for help. He made his living then using Autocad on property designs. One day he got appendicitis, died in Kaiser Permanente care, his wife told me.