I decided to clean up a bit (old story) and found a turboboard that I can not find back in the Big Book. It fits in the 68000 space of my A500 but it does not boot. The little board has got an MC68020RC16 and an MC68882RC25A and on the side of the board I read : TS68020. Google tells me :
"Hcmos 32-bit Virtual Memory Microprocessor - Atmel Corporation
The TS68020 is the first full 32-bit implementation of the TS68000 family of micropro- cessors. Using HCMOS technology, the TS68020 is implemented with 32-bit Registers and data paths, 32-bit addresses, a rich instruction set, and versatile addressing modes. By ATMEL Corporation"
So it belongs to the TS68000 family. Wikipedia tells me about that : "Thomson TS68000 (=Motorola MC68000)."
And here ends my info. Any bright ideas ?