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Changing screen resolution in OS9

thetcutkid

thetcutkid

macrumors member
Original poster
Jan 13, 2019
46
22
UK
I've been experimenting with hooking my G4 Sawtooth up to a flat panel TV via VGA.

The G4 has an ATi Radeon 8500 Mac Edition installed.

Under OSX, if I go to system preferences, display, I get eight different refresh rate choices per resolution, ranging from 60hz-120hz.

I've selected 1024x768 60hz and the desktop size etc. is perfect.

If I boot into OS9 and go to the monitor settings on the control strip, my choices are drastically limited, only one has a 60hz refresh rate and that's a resolution of 640x480, so the desktop is all over the place.

The resolution of 1024x768 has a refresh rate of 120hz and obviously doesn't work on my TV.

Why are my resolution options so limited under OS9 ?

I've tried to directly access the graphics card via the ATi menu (thinking I may have further options there), however, it keeps asking me to 'enable popup menu keyboard shortcut on the keyboard shortcuts panel'. If I open the keyboard control panel, I can't see any such option to enable !

Any info would be greatly received, thank you.

Nick
 
What I don't understand is the difference in resolution options between OS9 and OSX.

This feels like it should be a hardware issue in terms of the graphics card supporting a resolution the TV can provide, which it clearly does under OSX.

Could it be a driver issue ?
 
Does your TV actually support above 60hz? I ask because I have seen OSX show resolutions and hz settings on some displays that aren't necessarily supported. I'm guessing things like that are partial incompatibility with the display's ROM.
 
I do remember a classic OS app years ago that would allow you to achieve display settings that your display can run, but are not being offered by the OS by default. No idea what the name is though.

Anyone know the name?
 
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I've just happened upon it whilst Googling the problem lol.

I'll download it and see how I get on.
 
Do you have the correct OS 9 drivers installed?

These would load as System Extensions and such.

Take a look here: https://gona.mactar.hu/ATI_Mac/

Farther down the page is one specific for the Radeon 8500.
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thetcutkid said:
I've just happened upon it whilst Googling the problem lol.

I'll download it and see how I get on.
Click to expand...
Be careful with SwitchRes. I had it installed on OS X once and had a devil of a time getting rid of an errant profile and it's malfunctions once I removed it. Maybe not the same on OS 9 but something to watch for anyway.
 
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eyoungren said:
Be careful with SwitchRes. I had it installed on OS X once and had a devil of a time getting rid of an errant profile and it's malfunctions once I removed it. Maybe not the same on OS 9 but something to watch for anyway.
Click to expand...

Thanks for the heads up, will check drivers first.
 
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OS 9 can generally be weird in that regard (I know my 1080p monitor will only show up to 1680x1050 in OS 9 where OS X will show and can do full 1080p over VGA on that monitor)

but it also worth mentioning, make sure your using a modern VGA cable some of the really old ones dont have all the pins for EDID etc, as such the computer will just assume a generic VGA CRT is attached and you may not be able to chose the right rez/hz combo for your monitor.
 
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OK, so I'm a bit confused...

Where in OS9 should I be checking for an installed ATi driver ?

Secondly, for the current extension set I'm using, extensions manager is showing 'ATI Extension' checked, with a version number of 2.8.5, 'ATi Driver Update' and 'ATI Graphics Accelerator' are both unchecked.

OS9 ATi extensions.jpg
 
The ATI ROM Xtender is normally the one needed, just make sure you are using that latest version you can get.

The ATI Driver Update, I think can also preform same of what the ROM Xtender does.

Here in basic terms is what they do, on the graphics card itself, you have an FCode ROM that has a Native Device Driver 'NDRV' for Boot Services and the Mac OS Runtime Drivers.

The ROM Xtender can override this graphics card 'NDRV' with a newer version, a way for ATI to fix issues without updating the FCode ROM of the Graphics card.

Normally the latest update would be ATI OS 9 Mac Software Update January 2005, however there is a later OS X only ATI Driver package that installs a newer ROM Xtender that can be used in OS 9.

Also, I can make a custom 'NDRV' for any ATI graphics card using the last set of 'NDRV's for Leopard 10.5.8. These may or may not fix your issue.
 
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Thanks very much for the replies, I'm feeling a bit out of my depth tbh.

If I look at the extensions on my mac compared to the extensions listed on that Jan 2005 update, some of my extensions are older.

What's a bit confusing is that if I look I under system, library, extensions, everything connected with ATi has a date stamp of Jan 2005?
 
OK, so I've continued to experiment a bit and when I was out this morning also picked up a DVI to HDMI cable, as I was interested to see whether this would sharpen up the image a bit as there is some very small text in some of the production software screens which was a bit fuzzy when viewed using a VGA connection.

Needless to say the DVI-HDMI lead has improved the sharpness considerably but of course, inevitably it seems :rolleyes::(, has also created another problem...

Booted into OSX, the desktop is now fractionally too big for the dimensions of the screen - the top half of the menu bar goes off the top of screen and the bottom third of each icon in the dock goes off the bottom of the screen - changing resolutions doesn't help.

(The zoom function under Universal Access is turned off, I checked).

Booted into OS9 it's slightly worse, the menu bar is almost completely off at the top, the expanded control strip is much the same at the bottom and the drive/partition names are slightly off the right edge of the screen.

There is no fine adjustment available on the TV itself.

Weirdly, using DVI-HDMI, I now get the same resolution choices in both OS9 and OSX, the resolution I've got it set to at the moment under OS9 completely disappears (I don't mean greyed out, it just isn't there!) if I disconnect the DVI-HDMI lead and reconnect the VGA lead.

Is there anyway of fine tuning the desktop size from within the mac ?
 
thetcutkid said:
OK, so I've continued to experiment a bit and when I was out this morning also picked up a DVI to HDMI cable, as I was interested to see whether this would sharpen up the image a bit as there is some very small text in some of the production software screens which was a bit fuzzy when viewed using a VGA connection.

Needless to say the DVI-HDMI lead has improved the sharpness considerably but of course, inevitably it seems :rolleyes::(, has also created another problem...

Booted into OSX, the desktop is now fractionally too big for the dimensions of the screen - the top half of the menu bar goes off the top of screen and the bottom third of each icon in the dock goes off the bottom of the screen - changing resolutions doesn't help.

(The zoom function under Universal Access is turned off, I checked).

Booted into OS9 it's slightly worse, the menu bar is almost completely off at the top, the expanded control strip is much the same at the bottom and the drive/partition names are slightly off the right edge of the screen.

There is no fine adjustment available on the TV itself.

Weirdly, using DVI-HDMI, I now get the same resolution choices in both OS9 and OSX, the resolution I've got it set to at the moment under OS9 completely disappears (I don't mean greyed out, it just isn't there!) if I disconnect the DVI-HDMI lead and reconnect the VGA lead.

Is there anyway of fine tuning the desktop size from within the mac ?
Click to expand...

I'm convinced that your problem is on the TV side of things. I used to have similar problems hooking up an Intel Mac Mini and a PowerBook G4 to my Hitachi plasma TV. There was no fine tuning available on my set either, but in fiddling with the menu options I discovered a setting for aspect ratio. It wouldn't allow me to set a custom ratio, but did have a number of presets from which I could choose. For some reason, there were two different presets for 16:9, and the TV always defaulted to option #1. I found that when I changed it to 16:9 option #2, everything appeared on screen as it should.

The problem, and solution, was the same for me regardless of which Mac I was trying to connect, regardless of which OS I was using (Tiger; Leopard; Windows 7; Ubuntu Mate), and regardless of what display settings I attempted on the Mac. In my case, it was clearly the TV.
 
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I find it odd that the addition of the dvi-hdmi lead, despite undoubtedly improving the quality of the image, has thrown this additional quirk into things.

Connecting the mac via VGA, I get some very basic picture adjustment options under the settings menu of the TV, two of which allow me to move the entire picture up/down or left/RIGHT (not that I need to, as the desktop is aligned correctly using VGA).

If I remove the VGA cable and use the DVI-HDMI cable instead and bring up the same picture settings menu on the TV, all those options have disappeared.

I nearly bought the same model of TV on eBay this morning to use as a dedicated monitor, thinking that the new cable can only improve things lol, I think I'll give up.
 
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