Funny as I just recently hooked up these two drives to my A2000! They work fine. I have two internal drives and the 1010 and 1011 daisy chained. Maybe the P/S on the A500/1200 does not power both drives properly?
The Amiga 2000 has a 200watt power supply, it shouldn't have any trouble. Amiga 500 was 30watt.