Missing Monitor Settings, Display Resolution

greendansf · #1 December 7th, 2006, 03:36 PM

I hope the collective wisdom of this forum can help with this problem that I just started having.

I have a Sony Trinitron Multiscan 500 PS plugged into my Power Macintosh 7500/100. (The PMac has a 297MHz PowerPC G3 card.) The monitor and machine have worked together without problems for a looong time.

Yesterday I unplugged my monitor and removed the PC-Mac monitor adapter to use on a different monitor that was plugged into a beige G3 tower. When I reattached the adapter to my Sony monitor, plugged it back into my PMac and booted up, the screen size was greatly reduced!?

I opened the "Monitors" control panel to find that only 640 x 480, 67Hz was available. I'm pretty sure that this monitor was working at 1024 x 768 until today.

How can I get my old monitor settings back?!

Thanks,

Dan

greendansf · #2 December 7th, 2006, 09:07 PM

A friend suggested I try zapping the PRAM, which I did, but the monitor is still at the 640x480 setting and no other options are available in the Monitors control panel.

I understand why a failed PRAM battery would cause the machine to lose its settings, but in the past a machine with a dead PRAM battery has also lost the date and time, and that's not the case now.

Also, wouldn't the other resolution options still be available, regardless of the PRAM battery's condition?

This is frustrating.

sinclair_tm · #3 December 8th, 2006, 05:11 PM

are there any switches on the adaptor that may of gotten changed? also, there should be the option to show all settings, and only recommended. goto all settings, and pick the 1024x768 at 60hz.

Texas Mac Man · #4 December 12th, 2006, 05:50 PM

Try resetting NVRAM. See Mac PRAM, NVRAM, CUDA/PMU & Battery Tutorial
http://www.geocities.com/texas_macman/pram.html

Cheers, Tom

dlbk · #5 March 16th, 2007, 10:01 AM

Hi -

I'm having th exact same issue - after no problems for almost 3 years, this happened recently. I read where shutting down completely could fix it - and voila! It did! But now it's happening again and shutting down didn't bring back my res options. I tried the NVRAM reset and that also didn't work.
Has any one else found a solution to this? Any thoughts?

Thanks,
Deb