I got my ACA620 a couple of weeks ago, and my first impressions were very good (it is really fast, and I really love the maprom feature), but I'm also experiencing the same issues described here:
- The workbench is very stable and works well, but after a while some graphic glitches start to appear after a while in interlaced modes only (small colored lines appear randomly on windows) - I don't know if this problem is related to the ACA620 or the Indivision ECS or anything else.
- I was unable to get any WHDLoad game to work - which were working well without the ACA620 - (I tried with versions 17 and 17.1): some did some "Illegal instruction" crashes, some other freezed the Amiga totally.
So I started to mess around with ACATune options and WHDLoad options. Most options had absolutely no effect, by things went a little better with the NoMemReverse flag set in WHDLoad. As I understand it, this option forces WHDLoad to allocate memory in lower addresses instead of higher addresses.
I did some tests with Dynablasters: Without the NonMemReverse, the game froze the Amiga on the title screen. With the option activated, I was able to play but it crashed with an "Illegal Instruction" after about 5~10 minutes.
I'll try to clean the CPU pins as someone suggested here and do some more memory tests.