68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
Any help understanding/troubleshooting a 6100 problem I have?
Posted by: macragge on 2025-05-07 09:14:15
Hello all!

Yesterday I got a new (old of course, so, new-old) 6100/60 I bought, which I connected to a monitor I have. The machine had an extra video card so I used the standard Mac video port that was there first, and the machine booted and worked fine. Used it for a couple of hours, powered off, returned today, and now there is no video (boot chime, sounds like it's - like yesterday).

After getting no signal, I also tried the "default" port (a "fatter" connection that seems to be the default for this machine) but same problem (no signal).

When I first started it today, I forgot to power on the display, but then after restarting etc. it still doesn't work (changed monitors and cables, and the monitors and cables I tested works fine today with, for example, my 7300.

Any tips on things I could try, and if there's a chance that it's not broken but that something else happened?

I have no idea about the history of this machine - bought it from someone who has never used it and bought it some time bak thinking it was a PC.

Appreciate any input on things to try, and apologise for the newbness here!
Posted by: croissantking on 2025-05-07 09:21:02
It’s the flat or missing PRAM battery that causes no-video on these machines if I’m not mistaken. As a workaround, you can try resetting the machine quickly after power up.
Posted by: macragge on 2025-05-07 09:37:16
Ah, thank you very much! That would be the [Command (⌘) + Option + P + R] approach?

Seems the batteries are cheap and easily available still, so if that's the problem that would be great!
Posted by: croissantking on 2025-05-07 09:39:14
Ah, thank you very much! That would be the [Command (⌘) + Option + P + R] approach?
I think you power it on, then quickly off and on again.

Seems the batteries are cheap and easily available still, so if that's the problem that would be great!
Yeah, the 6100 is definitely one of those machines that can’t be run without a PRAM battery and I know it specifically affects video output. The other is the LC475, there may be others.
Posted by: macragge on 2025-05-08 10:11:37
Thank you very much for the help! Resetting by on-off-on worked like a charm, and a new battery has been ordered😄
Posted by: croissantking on 2025-05-08 10:37:46
Ha, I’ve never even used one of these machines, I just assimilated that tip over the years!
1