A590 vs Kickstart 1.3 questions

[Zac67]

Zorro fastmem runs from 0x200000 upwards, so with a mask of 0x0FFFFE you'd get word-aligned chipmem only. Since you've got no accelerator mem within 24 bit address space, you'd use a mask of 0xFFFFFE, i.e. any word-aligned memory withing the first 16 megs. RAM priority will take care of using fastmem first.

[Zac67]

Sounds like you wired your RAM expansion for 1 MB chip (rather than 512K chip, 512K ranger) - but your Agnus can't handle it... That way you just get trashed graphics and a crashing system. If you configure 1 MB chipmem, ensure your Agnus is up to it (or replace it).