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doclee · Sep 5, 2001, 09:46 PM

Sonnet just released patches that will let me upgrade my PowerMac 7500 with an upgrade card to OS X. When I did this, I found that I can only get 640x480 at 66Hz Refresh. Is there a way around this? I am accustomed to setting my monitor (AppleVision 17'') to 1152x870 at 75 Hz. Thanks for any help.

Sep 5, 2001, 10:08 PM

I have found that keeping the monitor disconnected from the CPU on startup will yield you an array of monitor sizes and refresh rates.

I too have the problem (minus the sonnet card) with NEC Multisync XE21 and cannot get the desired 1152x870 75Mhz without ALWAYS keeping the monitor disconnected at startup and plugging it in about 2 minutes into the boot up.

I hope to God 10.1 will have this problem resolved...

Good luck.

Aussie John · Sep 6, 2001, 04:28 AM

Asides from the screen how does it run?

tomfrit · Sep 6, 2001, 06:16 AM

i had the same problem and found it was in the cable - i plugged another cable (bnc) in and had all the resolutions i needed...

doclee · Sep 9, 2001, 02:22 PM

Originally posted by Aussie John:
<STRONG>Asides from the screen how does it run?</STRONG>

Seems to be fine otherwise.

Cowdog · Sep 9, 2001, 06:15 PM

I have the same thing happen to me sometimes on my dp g4.. and thought I'd note I installed 5g40 today and had the same unrecognized display problem but instead of just giving me the one 640 x 480 resolution it gave me all resolutions, even some my display doesn't do, and I was able to switch out of it.

Sep 10, 2001, 04:53 PM

I've had the same problem after my machine crashes and have been on the phone w/ Apple a number of times re: this and a few other issues w/ my G4 500/DP. I still haven't gotten a straight answer from them as to whether it is hardware or software, but they did give me two 'workarounds' and a bunch of excuses.

Workaroud 1 - crawl under my desk and unplug my monitor from the CPU every time I restart my machine. Unforntunately, for me anyway, its not practical as my machine crashes way too ofter.

Workaround 2 - on the monitors physical setup, turn DDC off. On my Apple Studio Display: Setup->ETC->DDC->OFF. From what I gather, this how the monitor tells the OS what resolutions it support. Unfortunatly, if I go this route, I cannot get my highest resolution (1600x1200) without rebooting with the DDC turned on. Not that I use it often, but its enough of a hassle when I do.

Luckily - with 10.0.4, my machine has become stable enough to use and crashes and kernel panics are becoming less of an issue.

Sep 10, 2001, 05:00 PM

I've had the same problem after my machine crashes and have been on the phone w/ Apple a number of times re: this and a few other issues w/ my G4 500/DP. I still haven't gotten a straight answer from them as to whether it is hardware or software, but they did give me two 'workarounds' and a bunch of excuses.

Workaroud 1 - crawl under my desk and unplug my monitor from the CPU every time I restart my machine. Unforntunately, for me anyway, its not practical as my machine crashes way too ofter.

Workaround 2 - on the monitors physical setup, turn DDC off. On my Apple Studio Display: Setup->ETC->DDC->OFF. From what I gather, this how the monitor tells the OS what resolutions it support. Unfortunatly, if I go this route, I cannot get my highest resolution (1600x1200) without rebooting with the DDC turned on. Not that I use it often, but its enough of a hassle when I do.

Luckily - with 10.0.4, my machine has become stable enough to use and crashes and kernel panics are becoming less of an issue.

Sep 10, 2001, 05:16 PM

Just curious -- do you turn DDC 'off' through a software program running on the Mac, or do you physically press the buttons on the monitior -- "menu, setup and the like'' to manipulate this setting?

Oneota · Sep 10, 2001, 08:01 PM

DDC is controlled from the monitor's hardware settings, not from software. Not all monitors use DDC, so there may not be an option to turn it off.