11 Replies Latest reply: Jan 8, 2013 11:39 PM by Appaloosa mac man Branched to a new discussion.
amiya.sahu Level 1 Level 1

Hi All


  How to change the display of mac os 7.1 so that it can accomodate 60 hz video frequency (Like Windows system display setting) ?

Please guide me .



  • varjak paw Level 10 Level 10

    On what model of Mac?

  • amiya.sahu Level 1 Level 1

    Quadra 950

  • varjak paw Level 10 Level 10

    It's been a long time so I may be misremembering, but I don't remember OS 7.1 having a native option to change the monitor frequency. If it does, it would be under the Options in the Monitors control panel. There were at the time a couple of third-party extensions that allowed more control over monitors, such as ActivateAllResolutions, but I can't find copies floating around the web any more. Someone else here may be able to offer other suttions.



  • Appaloosa mac man Level 5 Level 5

    Years ago a client had a used computer store.  We set up a quadra 950 with five video ports.  Each port was set to a different video option to illustrate different monitor sizes, settings and capabilities.  Just mentioned that to a store clerk today.


    First you go to control panels and open the monitor control panel.  Then check the settings and see if the monitor is recognized.  It is much easier to reconfigure if you have a nubus video card because then you do not have to reboot to find the monitor setting for the new monitor.  You may have to zap the PRAM to reset after failed attemps.


    My I ask if you have an apple monitor that you want to replace with a PC monitor?  If so, find a multi-sync monitor and go with it.  It will usually auto detect.  NEC made multi-sync monitors in the mid nineties that were very well behaved.  Other monitors required fussing but the NECs always lit up just fine.  Those crt monitors should be free or $5 at a recycler.



  • amiya.sahu Level 1 Level 1

    Thanks for your reply .It seems that you mentioned about add on graphics card. But in my case the display is managed by anative graphics controller(on board).



  • JustSomeGuy Level 3 Level 3

    Do you have a monitor that works (or doesn't work) now?  I'm trying to figure out what problem you're trying to solve.  I like the others don't recall a manual setting for the vertical scan frequency.

  • Appaloosa mac man Level 5 Level 5

    You have onboard video Plus the option for addon cards.  They are both controlled by the monitor control panel. 


    The question still stands, do you have a working monitor or are you trying to configure the monitor before you plug it in?  If you do not have a working monitor that shows the control panel, you are working blind.  You can hold the space bar while starting up some monitors but Apple adopted that key stroke for extension manager in later OS editions so keyboard start up configurations are specific to OS versions and Super Mac and Radius displays. 


    We can give you far more detail if you give us a little more information about the monitor you have now.  Multi-sync monitors are the only way to go if you are working blind.

  • amiya.sahu Level 1 Level 1

    many thanks for the inputs.


    Here is what i'm looking for. There is one monitor already connected and working fine and now i want to give output to another frame grabber application. So i've used a Y sliptter from the DB15 and gave connection to the monitor and the frames grabber card. Now the problem is that the frame grabber card installed in other system has to get input in a different frequency. So the catch is how to provide a different frequency other than the default one in OS.



  • Appaloosa mac man Level 5 Level 5

    Where is the frame grabber card installed?  A Y splitter will not allow for a different frequency.  A second video card will.


    Please tell us just what monitor you are using and the video setting you have set in the control panel.

  • amiya.sahu Level 1 Level 1

    the Quadra 950 has only one DB15 out to which the Y splitter was connected to accommodate the primary monitor and the card. Now the primary monitor is removed. The frame grabber card is installed in a windows machine and has DVI as input. The DB15 out from Quadra has a RGB split which is connected to a DVI converter in turn going to the input of the frame grabber card. Now we need to change the frequency to 50 Hz so that the card is compatible with the viedo output.


    many thanks

  • Appaloosa mac man Level 5 Level 5

    Thank you for the details.


    The next question to consider is the type of information on the hard drive that you would like to capture.  I am intrigued by the idea of a card that will transfer from one computer to the next.  It obviously is not a NUBUS card.


    Given a little more free time, we could unpack an 7.1 machine and test some settings, but until then, understanding the information source that you would like to capture would be helpful. 


    Will the software run on a 7.5.3 machine?  That OS gives you more options and will run a number of AV configured Macs.


    Finally, a low tec approach would be to film the source monitor to a newer media to overcome the lack of control over older hardware.