TiBook 667MHz 1152x768 to 1280x854 possible?

[Project Alice]

Hey everyone,
I stumbled upon this reddit post last night, where someone was replacing a display on their 667 and unknowingly got a higher res display.

As you can see it does work, but it isn’t outputting the resolution correctly.
Another redditer has been suggesting that it is impossible and won’t ever work unless you were to “reprogram” the GPU. This GPU supports up to 1920x1440.
We know there are other working mods like this such as the iBook G3 XGA mod, and the 1050x1400 12” PBG4 mod. Neither of which required a “reprogramming” of the GPU.

I believe the iBook XGA mod did need an open firmware command.

So, is this other person correct? I would be surprised if there is no way to use the DVI display on the VGA model if it is obviously able to fit and plug into the board and display something. Common sense tells me that since the display is technically working, it may need a similar open firmware command for it to recognize the resolution properly.

 

[Amethyst1]

Additional things I’d try:

1. Boot $SomeBSD, Linux, MorphOS or Mac OS 9. Does it do the same?

2. Check the active timing and the pixel clock limit reported by SwitchResX (SwitchResX requires at least Mac OS X v10.3.x Panther though). What resolution is the display being run at and is the pixel clock limit sufficient for a 1280×854 60 Hz timing (75.75 MHz or higher)?

On Mac OS X v10.2.x Jaguar, you can try DisplayConfigX instead.

3. If there's no 1280×854 timing, add a custom 1280×854 60 Hz resolution in SwitchResX using the exact timing parameters from the higher-res display’s EDID (which you can export in SwitchResX) — or from another 1280×854 display's EDID if it isn’t reading the EDID correctly for some reason. You can also try a 1280×854 60 Hz timing using the CVT-RB formula.

 

[Project Alice]

Additional things I’d try:

1. Boot SomeBSD, Linux, MorphOS and/or Mac OS 9. Does it do the same?

2. Check the pixel clock limit reported by SwitchResX. Is it sufficient for a 1280×854 60Hz timing?

3. Add a custom 1280×854 60Hz resolution in SwitchResX using the exact timing parameters from the higher-res display’s EDID, or another 1280×854 display if it isn’t reading the EDID correctly for some reason.

I linked the OP to this reply. Hopefully this will be more helpful to them.

I feel like this entire forum is usually more helpful than reddit lol

 

[Dronecatcher]

I feel like this entire forum is usually more helpful than reddit lol

I try to be helpful on Reddit but it is a genuinely life draining experience...

 

[B S Magnet]

Hey everyone,
I stumbled upon this reddit post last night, where someone was replacing a display on their 667 and unknowingly got a higher res display.

As you can see it does work, but it isn’t outputting the resolution correctly.
Another redditer has been suggesting that it is impossible and won’t ever work unless you were to “reprogram” the GPU. This GPU supports up to 1920x1440.
We know there are other working mods like this such as the iBook G3 XGA mod, and the 1050x1400 12” PBG4 mod. Neither of which required a “reprogramming” of the GPU.

I believe the iBook XGA mod did need an open firmware command.

It’s a multi-line OF command one can write to nvram from Terminal (and will be deleted if clearing with a Cmd-Opt-P-R reboot).

During boot, at least on the iBook running ATI Rage 128, the grey Apple/verbose portion of booting doesn’t display at XGA; only when handing off to WindowServer does the XGA resolution (set with that multi-line command) activate. Part of the nvram command is to trick the system into thinking it’s not a PowerBook2,2, but rather, a PowerBook3,1 (i.e., an XGA Pismo, which came out many months earlier and would be something that the final Open Firmware update for the M6411s, 4.1.7ƒ, would likely have referenced in a registry).

I’m unsure how other video cards/Macs from that 1999–2002 era would handle this OF hack… probably fine, but I’ve never tested it outside of the M6411, and for something like the PowerBook3,4 of the DVI 667MHz, it would probably need to “know” about another Mac of its period whose OEM resolution was higher — maaaaybe something like the PowerMac4,5 — i.e., the first 17-inch iMac G4 (though that model came out a few months after the PowerBook3,4).