Sometimes you are really lucky. Last summer I googled for fun after Amiga stuff and I found a seller close to me who wanted to sell four A500, one A2000 and one A3000 together with a couple of 1084 CRT-monitors. I could not resist since the price was relatively low. Anyway, turned out the A3000 was sold and the huge box he delivered to me contained no CRT-screens. I was slightly disappointed, until I noticed a switch on the side of one of the A500. Maybe a Kickstart switch? I ripped the plastic shell of the A500 open (not really) and found a huge card inside. Turned out it was a 030 board with a FPU and 4 MB fast memory. BBOAH gave me the answer, it was a Harm 030 board, or Hurricane or something.

Amiga 500 030 turbo