CompuServe Thread

John- I installed an A3640 CBM 68040 accelerator in My stock 16mhz A3000 several months ago. It works very well. However, getting the board and the A3000 built in SCSI port to function harmoniously was a nightmare. Also, I consulted with 4 authorized Amiga hardware techs before I did this. I got four different answers, none of which were correct from my experience: This was what I was told: 1. A3640 Only works in A4000 and A3000Tower 2. Should work. I guess. Yeah, it'll work. 3. Does not work in an A3000. Nope. 4. Works in some and not others. Reasons unknown. Here is what I did to make it work: First, I consulted 'Appendix E-1=> A3000 Schematics' in the "Introducing the Commodore Amiga 3000" Manual. I noted each jumper with a setting specific to the processor clock speed (16mhz or 25 mhz NTSC or PAL) and set the motherboard jumpers to the setting for (NTSC) 25mhz. Maybe 6 or 7 had to be changed. The real tricky thing was that thru lots of experimenting a dumb stroke of luck, I discovered that the A3640 & built in SCSI conflict could be resolved by using a PageMode Zip in at least the first (U852) Zip Ram socket, as opposed to a Static Column Mode Zip. Apparently, Page mode operation disables burst mode memory caching something 'er'other that the 68040 chip can use to run even faster, but that freaks out the A3000 SCSI. This was my experience. Yours could be different. Who knows. PS: Trouble was worthwile. Speed increase is SIGNIFICANT! GOOD LUCK, Charlie McC 70107,1506