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LC475 Power Question


I'm currently troubleshooting an LC475.

Should the machine start up when the power supply is switched on or should it use soft power like most other 040 machines?

This motherboard came to me with a destroyed R85 resistor. It's the big 6.8 ohm guy by the sound chip. I replaced it, along with the 47uF C161 back there, during the recap(PSU is also fully recapped and putting out correct voltages). When I flip on the power switch I get a Macintosh chime and the fan and HDD start going but nothing ever shows up on the screen. No grey or anything.

Just wondering if it should be turning itself on like that or if I have other issues to look into.


Well-known member
The LC475 dose not use soft power, however it is one of a few macs that actually need a PRAM battery installed otherwise you don't get video output

You can apparently get around this by swithcing it on, then of and on again quickly but I haven't personally had any luck doing this