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Resources for Crusty Old Sysadmins
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UNIX Crap
- Export and Mount NFS Shares

Network Crap
- Use a Raspberry Pi as a WiFi Router

SGI/IRIX Crap
- Basic SGI hardware info
- Installing Photoshop 3.0.1
- Installing Illustrator

Classic Macintosh Crap
- Mac Plus SCSI and using a BlueSCSI
- Mac IIci repair notes

Sun/Solaris Crap
- SunPCi cards

NeXT Crap
- Basic hardware info

Abandonware Resources

Macintosh IIci Repair Notes

Power On Problems
The power supply in the Mac IIci has one distinct shortcoming, that the soft power-on switch may not function as it did when new. This is apparently due to an aging diode within the power supply that "leaks" the 5 volt "trickle" circuit down to 0 (zero) volts as the computer sits. Once this happens, you might experience:

clicking if you hold down the power button on the keyboard or back of the case
inconsistent, seemingly random power on when the power button is pressed
strange pulsing noise from the fan or hard drive
nothing at all

Because the soft power circuit doesn't have enough zoobs to fully engage power-on, it may appear that the power supply is dead or your logic board has failed. This MIGHT not be the case, and there is a workaround: plug everything into a power strip that is turned off, so no power is flowing to the Mac. Once everything is plugged in and ready to go, turn on the power strip and immediately press the power button on the keayboard (not the case). My experience shows that this will work 90% of the time, because the circuit doesn't have time to leak down after being energized.

Once powered up, the computer can be restarted, rebooted, or soft booted - so long as you don't turn it off. If you have to turn it off, you need to unplug it (or turn off the power strip) and wait. Possibly wait for many, many minutes to allow everything to discharge and "reset" before trying to power up the system again.

There is a repair that can be done on the power supply, apparently, that will permanently solve the problem. However, I have not tested it and can't put it here until I verify that it works. Once I do, I'll create a new section on this page.

System Powers on, but the Screen is Blank
The IIci uses main RAM for video RAM - there is no separate RAM for display. It also will just plain refuse to function if it detects anything wrong with RAM upon initial boot, or rather, it CAN'T do anything without healthy RAM. An easy diagnostic is to pull all the RAM, clean the SIMMs and slots, and make sure everything is seated. The adventures in shipping most likely jostled something loose, even in a decently packed computer. If this fails, try known good RAM. If that fails, pull the cache card and try again.