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Enable additional resolutions and refresh rates System
Problem:

MacOSX doesn't allow all your screen resolutions if you don't have a display from Apple. For me, it would only allow me to run my iiyama 19" CRT at 75Hz, such that I could still see a little flickering. In MacOS 9, I didn't have this Problem. This was making me mad for as long as I have MacOSX installed.

Solution:

In /System -> Library -> Displays -> Overrides, I found some folders named "DisplayVendorID-[hex-number];" these contain XML files named "DisplayProductID-[hex-number]." These files contain the information the system uses to determine wich resolutions to allow. All you have to do is create your own display definition. The problem is, you have to find out what DisplayVendorID and DisplayProductID your display is registered as. If you have the Developer Tools installed, you can use "IORegistryExplorer" to find out. The path for me was IOService:/Root -> PowerMac3,5 -> MacRISC2Pe -> NVDA,DisplayB@1 -> .Display_NV-01108000 -> display0 -> AppleDisplay (I have a GeForce4 MX video card). [robg adds: I changed the "/" into " -> " so the lines would break.]

With the DisplayVendorID and DisplayProductID I found there, I created my own Display definition. I just copied this one: "DisplayVendorID-756e6b6e/DisplayProductID-9210" (this must be the definitions for a "Studio Display 21" by Apple) to a path containing the DisplayVendorID and DisplayProductID I found in the IORegistry. For the filename, the values must be in hex, and of course you have to be root to do that. Then I opened the new file and changed the values with key "DisplayProductID" and "DisplayVendorID" to the same values (but this time they must be base10 notation - not hex).

After restarting the computer, the OS now thinks it has an Apple Studio Display 21 attached and lets me set my Display to many more resolutions and refresh rates!

But WARNING!: As we all know playing around with display resolutions may be a dangerous thing! So if your old CRT goes up in flames ... or just black forever - I don't want to be held responsible!

[robg adds: Please heed the warning, as you really could potentially do bad things to your monitor with this hint! If you do manage to select an invalid screen resolution, you may be able to restore OS X functionality (if you didn't fry the monitor) with this hint. Also, a safer approach might be to try the method listed in this hint, and/or use the SwitchRes X application mentioned in the comments to that hint.]

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Enable additional resolutions and refresh rates
Authored by: rgray on Feb 17, '03 10:21:05AM

I second that warning - and not just with regards to the monitor. My
spouse blew up a video card playing with resolutions... No monitor
damage occurred but the vid card was a total loss... 'nuff said.



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Enable additional resolutions and refresh rates
Authored by: lrivers on Feb 17, '03 10:22:12AM

Just make sure to set the refresh or resolution to ridiculous values. 85 Hz is enough to prevent flicker. Check your monitor's stats to see what it can support and you should be fine...



[ Reply to This | # ]
Display Detected
Authored by: saint.duo on Feb 17, '03 11:12:05AM

I have an Envision 710e, and I have always had 7 resolutions to choose from. I believe these are the only 7 that my displays will support (they're pretty cheap monitors).
I have noticed that X will limit your display resolutions if it does not know what kind of display you have. When I go to displays in system preferences, the title changes to "ENVISION EN-710e". If something goes wrong, and it just shows "displays" or "vga display" then i only get 640x480, 800x600, and 1024x768 as choices.

---
--
duo



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Enable additional resolutions and refresh rates
Authored by: muecke on Feb 18, '03 04:58:40AM

Almost there...
Currently I use 2 CRT Monitors (21" and 22"), each capable of 2048x1536@75 attached to an ATI RADEON 8500 (dual G4 running Mac OS X 10.2.4). The first display is OK with 1600x1200@85, while I was not able to set the same resolution on the second one. After trying this out, I could at least set the second one to 1600x1024@85 instead of the same resolution at 76Hz. Better, but still not perfect. Nevertheless a very helpful tip.

Btw. both displays are now shown as 'Studio Display 21'.

Wolfram.



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Enable additional resolutions and refresh rates
Authored by: muecke on Feb 18, '03 06:35:55AM

The Vendor and Procut IDs of the currently configured monitor(s) can also be found in the file /Library/Preferences/com.apple.windowserver.plist



[ Reply to This | # ]
Enable additional resolutions and refresh rates
Authored by: prinzal on Mar 03, '03 05:37:34AM

Hi everybody,

>> I just copied this one: "DisplayVendorID-756e6b6e/DisplayProductID-9210" (this must be the definitions for a "Studio Display 21" by Apple) to a path containing the DisplayVendorID and DisplayProductID I found in the IORegistry.<<

my problem is, I can't find the path containing the Display Product and Vendor ID.

I found out the vendor ID (1460) and the product ID 17459, of my monitor. The monitor prefpane say: unknown monitor
I'm using 10.2.2 on G4 MDD 2x867 Mhz.
The monitor is a "Macom E96D 21''

many thanks for help

prinzal



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Enable additional resolutions and refresh rates
Authored by: 47ronin on Jul 09, '03 10:00:04PM

Can you please explain this hint in English? I got lost where you started looking at DisplayProductID and hex values.. wtf where do you find out what hex value is supposed to be used? How? I need a more straightforward explanation please! Thanks



[ Reply to This | # ]
Missing monitor resolutions and refresh rates
Authored by: 47ronin on Jul 10, '03 12:27:50AM

Our company just received two MDD powermacs and one Sawtooth powermac. We also got three brand new ViewSonic CRT monitors (E90f+, E90f+sb, and E70f-2). All have Mac OS X 10.2.6 with all the updates. What doesn't make sense is that none of the Macs can get reasonable resolution and refresh rates, e.g. the 19" E90f+ cannot do 1600x1200 85Hz even though in OS9 we can choose it. I can only get 60Hz at that res and only 75Hz @ 1280x1024. There are no additional modes available even when "Show modes recommended by display" is unchecked. The 17" ViewSonic can only max out at 1280x1024 60Hz which is totally unacceptable.

What happened to the additional modes? In Mac OS X 10.1 there was a way to select "unsupported" resolutions. However, these resolutions are not invalid, as the Radeon 9000 cards in each of the new Macs can easily output much better modes.

We briefly tried SwitchRes X but it didn't work at all. It looked promising but nothing happened when we attempted to add extra modes. Nothing new appeared in the Display menu. There isn't even any real documentation that explains what the yellow triangles or checkboxes are for.

We tried booting with the monitors off and only turning them on when the Mac was fully logged in. Even then, when you pull down the Display menu with the monitor on, the model# appeared, as if the Mac figured out the type when the monitor powered up. There's no way to fool this accursed auto DDC!!

Macosxhints.com had a thread about editing some System display library files using information from IORegistryExplorer but the discussion became way too cryptic to be practical.

We even tried using the Detect Displays button while the monitor was powered down, then turning them back on after 15 seconds so that the Mac would be fooled into thinking there was a generic VGA installed. That failed. The Mac pulled a DDC profile as soon as the monitor was turned on.

There HAS to be a way to select valid, but greyed out resolutions! This situation is making me look bad for choosing Macintosh for our business.



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Missing monitor resolutions and refresh rates
Authored by: vikash on Oct 04, '05 12:12:58PM

The documentation for Switchres is in Readme file which is in your applications/Switchres folder. If it's not there try reinstalling the application. Also see my post in the thread below about this program's strange behaviour.

http://forums.macosxhints.com/showthread.php?t=34122&highlight=refresh+rate

Try creating Custom resolution it might do the trick.



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Enable additional resolutions and refresh rates
Authored by: daran on Nov 19, '03 04:43:57PM

There is a commercial tool available to do this in a more safe / elegant manner. That features auto detection and more resolutions as well as 100Hz everything (given your hardware supports that). If you've got 12 bucks to waste, checkout

http://www.3dexpress.de/displayconfigx

BTW: I wrote that shit:-)



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