I think the E3 uses 16 x BM1680 Neuralprcessing Chips and one Asic or FPGA for the controlling.
If the E3 has 6 cards, I must correct myself:
6 cards with 2 x BM1680 + 1 FPGA or ASIC each
That´s 12 x BM1680 + 6 x FPGA or ASIC.
Or 18 x BM1680 and one Asic or FPGA for the controlling, if Bitmain connect the BM1680 with each other.
Even Bitmain sell a card with 1 x BM1680 and FPGA since January. They announced a card with 2 x BM1680 and FPGA.

Why are people even talking about the Bitmain AI chip and this thing?
That chip is optimized for FLOATING POINT operations, like any AI chip - it is NOT going to process INTEGER operations very well like mining requires, NOR is it going to be efficient at doing so.
The BM 1680 is NOT A MINING CHIP and is not going to offer decent performance per $ or watt since the bulk of the chip would go to waste AND WASTE SOME POWER if someone tried to mine on it.