Pitou Report post Posted February 7, 2017 Hello, I have a Mac IIfx that I just recapped. I now turns on, but I get no chime/sound at all. I tested the ROM SIMM and RAM simms in another Mac and it's fine. Any ideas/pointers? Thank you. Pitou! Share this post Link to post Share on other sites
mac-man6 Report post Posted February 9, 2017 Are you sure the speaker was reconnected after recapping? Share this post Link to post Share on other sites
Pitou Report post Posted February 13, 2017 Yes the speaker was connected. I am lucky enough to have another logic board. I replaced many logic chips and still no luck. I'm thinking the main 68030 CPU might be blown. It happened before on another Mac II. I played around with the scope, but it's a bit hard without the schematics. I'll hunt for a new CPU. Do you know if I should at least get the startup chime *without* the 68882 co-processor? Also, to get it, I must have at least for banks of RAM filled. Is that right? Thank you. Pitou! Share this post Link to post Share on other sites
CelGen Report post Posted February 18, 2017 Minimum of one bank of ram filled but no idea bout the missing processor. Verify you don't have leak damage somewhere. Share this post Link to post Share on other sites
zuctronic Report post Posted February 22, 2017 Any update on this? I have the same issue with a Mac IIfx. Share this post Link to post Share on other sites
Pitou Report post Posted February 24, 2017 I replaced the CPU but still the same. I'm about to try a new 68882 FPU. My guess is that the fx needs both the CPU and FPU in order to boot what's in the ROM SIMM. Will let you know. Pitou! Share this post Link to post Share on other sites
zuctronic Report post Posted February 25, 2017 Ah, in my case it turned out to be the ROM. I tried a ROM-inator II from BMWOW and it's working now.So now the question is: Is it possible to repair the bad ROM? How do I go about troubleshooting it? I don't see any replacement Mac IIfx ROMs available anywhere but I'm interested in restoring OEM parts as much as possible.. Share this post Link to post Share on other sites
techknight Report post Posted February 27, 2017 (edited) if the ROM is bad, then it COULD be suffering from bit-rot if it started life as a PROM so it works exactly like EPROM but with no window. So you burn it and its done. if its mask-ROM its likely something different like failing buffer circuits etc internal to the IC. Edited February 27, 2017 by techknight Share this post Link to post Share on other sites
zuctronic Report post Posted February 27, 2017 (edited) I took a closer look at the Apple ROM SIMM and noticed the contacts were looking pretty dull. I wiped them down real good with some IPA and now it's working fine!P.S. - A/UX doesn't boot with ROM-inator II Edited February 27, 2017 by zuctronic Share this post Link to post Share on other sites
Pitou Report post Posted March 9, 2017 I'm now getting the startup chime. However after a couple of seconds, I get another sound/chime. I tried the RAM simms in another MAC and they are good. Can you tell me what it could be related to? Thank you. Pitou! Share this post Link to post Share on other sites
