All You Ever Needed to Know About the Apple M3502 21" Colour Fixed Frequency Display

This page is an aid to all you lot out there who have an Apple 21" Fixed Frequency Display (family number M3502) and needed to know more about it. This page includes info on setting it up for use on a Linux or Windows 95 system, plus pinouts, cable requirements and monitor specifications.

Please note: The author of this page cannot be held liable for any damage or consequences arising from the use/misuse of the information contained within this document.

Using an Apple M3502 21" Fixed Frequency Display In Linux (Redhat 5).

The Apple M3502 is a lovely 21" Fixed Frequency display with Sony Trinitron Display. It would be a shame not to be able to use such a beauty on a PC, and just let it sit by the way, testimony to the outdated and outmoded computers it once supported. So, to get it to run on your Redhat 5 system, this is what you need, and what you have to do:

• Firstly, your graphics card will have to be able to support the resolution and refresh that the monitor works at, which happens to be 1152x870 at 75Hz. I got it to work on a 1mb S3 Trio64V+. However, the higher spec S3 Virge cards don't seem to be able to support that resolution (actually, this probably isn't the case - read the section on setting up the M3502 in Windows 95). If you need a new graphics card, the ATI's seem like a good option (the @ Work or @ Play), and they should support the resolution the monitor runs at.

• You will need the right monitor cable. I used a genuine Apple cable (13w3 Male to Mac 15 pin socket) with a genuine Apple to PC display adapter (15 low density to 15HD). Bear in mind that the 13w3 pin outs have been tampered with on this monitor, so you cannot use a generic 13w3 to Mac or 13w3 to PC cable (The red and the blue signals have been swapped around - see below for the pin outs on the M3502). Luckily for us, we don't need a sync combiner because the Apple uses separate sync! How convenient - perhaps it wants to be a PC display after all....

• Before we go any futher, may I recommend backing up the configX configuration file in /etc/X11/ called XMetroconfig (if you have MetroX installed - it might be called something else if you are using xfree86), just in case things go wrong. There is another file called xconfig.tmpl, which you might want to back up, but I can't remember the directory it is in. Do a 'locate' to find it and back it up. Right - boot up your Linux system as normal, with your usual display attached. Now run configX program.

• For your adapter type, make sure Generic S3 Trio is selected (or whatever card you may be using). Then for display type, select Sony GDM-17SE1 (I know it is a different monitor, even a 17 incher, but it seems to work). Enable the resolution 1152x900 and set it to 75hz. You can even enable 1024x768 resolution at 85Hz!

• OK, quit configX and save the changes. Now edit the file /etc/X11/XMetroconfig (or wherever your "Modelines" are stored for configured monitors). Look for the line that starts "Modeline 1152x900..". The hsync and vsync will both be '+'. Change them so they read '-hsync -vsync'. Save the file.

• Right, now hook up your Apple M3502, and type startx (by the way, you will never get text mode on the monitor using this method - if you want text mode desperately, you can invest in a dedicated graphics card for fixed frequency displays, though these are expensive). If all bodes well, you should have a lovely 21" display doing the business. If you get fuzz, hit Ctrl, Alt and - to send it into 1024x768 resolution. You should hopefully get a picture. If you still get fuzz, then, erm, don't blame me - be quick and restore your backed up XMetroconfig and xconfig.tmpl files (you did back them up didn't you?).

• If it works, then run configX within X Windows to centre the display. If you are getting a display that is brown and red in colour, and off centre, you haven't set the polarity ( the hsync and vsync bit ). Make sure they are both set to '-' in XMetroconfig. If all fails, try using the Sony GDM-20SE1 monitor in configX, since I managed to get an excellent display with this setting too.

Just for reference, the M3502 has an official horizontal scan of 68.7 khz, and a vertical refresh of 75hz, and a bandwidth of 100Mhz at 1152x870 (the "official" resolution). The horizontal and vertical frequencies are displayed in configX. My monitor was running at 68.53Khz. horizontal and 76hz vertical.

Using an Apple M3502 21" Fixed Frequency Display In Windows 95.

To get your Apple M3502 fixed frequency display running on Windows 95 you'll have to do this (read the notes above since these are also relevant):

Firstly, get hold of a copy of Scitech Display Doctor 6.5 http://www.scitechsoft.com/. Providing that your card can support 1152x870 at 75hz, you should be able to configure Display Doctor to run at 1152x870 75Hz, with negative sync on the horizontal and vertical (all these settings can be adjusted via Display Doctor, providing you use Display Doctor's video driver - Display Doctor also has presets for Fixed Frequency monitors). This seems to work, probably because Display Doctor looks like it can get your graphics card to do incredible things. If you can't get it to work, you might want to check out this page on getting Sun fixed frequency displays to work in Windows 95. It is at http://www.iaehv.nl/users/leibbran/sunmon/sunmon.htm. I am running my M3502 display on an S3 2mb Virge DX graphics card, and am getting excellent disply quality (albeit in 1152x864 in thousands of colours only), thus dispelling the myth that the Virge can't do 1152x864.

The Settings to Use in Scitech Display Doctor 6.52

Right, the best settings to use in Display Doctor are as follows (please note that these settings work with the Apple M3502 fixed frequency display and may not work with other display types):

Firstly, you need to select "(Fixed Frequency Monitor Types)" from the list of monitors. Then, if you want to run it in 1024x768, make sure the following settings adjustments are made:

Minimum and Maximum horizontal scan rates must be 66 and 70 respectively, and min and max vertical scan rates must be 70 and 90 respectively. Also make sure the hsync and vsync check boxes are both checked. Timing calculations must be Discrete.

If you want to run the monitor at its proper resolution (1152x864 - giving you more screen size) then make sure the following adjustments are made:

Minimum and Maximum horizontal scan rates must be 66 and 70 respectively, and min and max vertical scan rates must be 60 and 80 respectively. Also make sure the hsync and vsync check boxes are both checked. Timing calculations must be Discrete.

Once these settings have been entered, you can adjust the screen display to your liking by using the Centre Screen facility in Display Doctor. When using the Centre Screen facility, make sure you use the 84 Hz option for 1024x768 and the 75 Hz for 1152x864. If these frequencies aren't listed then you have either not entered the horizontal and vertical scan rates correctly, or your card does not support that frequency at the said resolutions (in which case, you will have to buy a higher spec graphics card, though bare in mind, my S3 1mb Trio can do it so I am sure most cards should be able to cope!).

A useful tip from Frank van 't Veer told me that you may have problems getting the resolution to 'stay' after you have centred the screen in Display Doctor. To get round this you have to change the refresh rate in the advanced settings of Display (in control panel) from optimum to standard or default adapter. Also, make sure that you are using the Display Doctor driver not the Windows one, and that the resolution in Display is set to 1024x768 or 1152x864. Thanks Frank!

Specs for the Apple 21" colour display M3502 are as follows:

Pinout Diagram for the Apple M3502's 13w3 female connector (c) 1992 Apple

Diagram of a standard 13w3 connector with pinout table for differing monitors

13W3-SGI Monitor Pinouts ================

pin A1 - Red/R-Gnd

pin A2 - Green/G-Gnd

pin A3 - Blue/B-Gnd

pin 1 - monitor type 3

pin 2 - monitor type 0

pin 3 - Composite Sync pin 4 - H Drive

pin 5 - V Drive

pin 6 - monitor type 1

pin 7 - monitor type 2

pin 8 - digital gnd

pin 9 - digital gnd

pin 10 - sync 2 (hmmm, page 201 of the SGI Indy owner guide says pin 10 = gnd ?!?)

13W3-SUN Monitor Pinouts ================

pin A1 - Red/R-Gnd

pin A2 - Green/G-Gnd

pin A3 - Blue/B-Gnd

pin 1 - n/c

pin 2 - n/c

pin 3 - sense 2

pin 4 - sense ret

pin 5 - Composite Sync

pin 6 - n/c

pin 7 - n/c

pin 8 - sense 1

pin 9 - sense 0

pin 10 - C-Sync ret

What cable do I need to connect the Apple M3502 monitor to my PC or Mac?

What cable do I need to run this blasted monitor I hear you cry. Well, by the looks of things you will need a genuine Apple or custom made cable to get the M3502 to work correctly. The part number for the cable that works on the Apple M3502 display is 590-0615-A or 590-0615. You should be able to pick this up from companies on the net for about £23 ($50) - though expect to pay more if you are in the UK. Or you can get a genuine Apple cable from your local Apple centre for about £60 ($130) - ouch. I have recently purchased a second hand 590-0615 cable made by Apple, and that cost me £15 ($35). The 590-0615 takes you from a male 13w3 down to a male 15 pin Mac connector.You will need an adapter that converts a male Mac plug to a PC 15 pin HD plug if you want to hook up the display to your PC. These you can pick up relatively cheaply, and I think a bog standard third party brand will do the job as equally as an Apple branded converter. I got hold of a genuine Apple Mac to PC adapter for £12 (about $27) and this works fine. The product code for the Apple adapter is 590-0322-A. By the way, if you have a PC to Mac converter lying around, and the genders are wrong, then don't attempt to use gender changers on it, because they won't work. You have to get a Mac monitor to PC converter, the PC monitor to Macintosh converters are different.

To find companies that sell 590-0615 cables, do a search for 590-0615 from http://www.hotbot.com/ - the other search engines didn't seem to pick up as much as Hotbot.

Other Useful Links for getting your fixed frequency display to work:

http://www.andrew.cmu.edu/user/bs56/new/comp/fixedfreqpc.html

http://rugmd0.chem.rug.nl/~everdij/hitachi/hodgers.txt

http://rugmd0.chem.rug.nl/~everdij/hitachi.html

http://www.devo.com/video/ - this is the fixed frequency video FAQ

Can you help me?

OK, I have a couple of questions about the Apple M3502 and was hoping that someone out there could answer them.

I have heard the M3502 is a rebadged Sun display. Does anyone know the model of the Sun display that is inside the Apple case?

Also, is there anywhere on the net that specialises in second hand fixed frequency monitors, including the Apple M3502 to buy?

If you know any of the answers to the above, send a stamped addressed envelope to mailto:s_c_spice@yahoo.com (s_c_spice@yahoo.com)