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#1 2014-05-30 05:06:11

From: Sf, Mi
Registered: 2014-05-15
Posts: 956

Power Macintosh 6100 no video when powered on.

There are some select Vintage Macintosh models that can give this issue when the Pram Battery is dead or low

Apple talks about the problem here:

Macintosh models which can be affected: Quadra 605, Performa 475, Performa 476, LC 475, Centris 660AV, Quadra 660AV, Power Macintosh 6100, and the Performa 61XX computers.

You can fix this issue by installing a fresh pram battery. 1/2 AA 3.6 Volt.
Or You can do what is called the " Flick Trick "
Turn it on, Then back off, Then Back on Kinda quickly.
And The machine should power up with Video even with out a pram battery installed.

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#2 2014-05-30 05:46:31

From: Corvallis, OR
Registered: 2014-05-12
Posts: 1,022

Re: Power Macintosh 6100 no video when powered on.

Good to know. This was driving me nuts the other week until I remembered that 6100s were effected by it.

Daily Drivers: 27" iMac 2.8 GHz Quad-Core i7 (Late 2009), 21.5" iMac 2.7GHz Quad-Core i5 (Late 2013), 11" Macbook Air 1.6 GHz i5 (Mid-2011)
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#3 2015-07-07 16:57:02

From: Germany
Registered: 2015-07-07
Posts: 22

Re: Power Macintosh 6100 no video when powered on.

My 6100 did a similar thing but in a more vicious way: it would boot from the monitor it was attached to the last time it booted but it would not boot from any other monitor (type). The one that worked was a Potrait Display.


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