Difference between A520 vs GBS8220 looks like SD vs 4K
I'll try AD724 later too.
I did the shielding too, seems fixed some problems but jailbars are still visible somehow.
Grounded shielding didn't make any difference for me. I should put a small 5V fan on the heatsink too.
No way to get rid of the annoying deinterlacing of GBS?
I also found this, not sure if it works with amiga or not:
http://www.hollandcomputers.com/stor...ors-p10889.htm
Edit: I recommend to add a 5V fan on the heatsink. That big chip makes the whole board hot.