Member Avatar for J Daniels

I have a G4 sawtooth 400 with a ATI RAGE 128PRO and I've got two monitors connected to it. A VGA and a DVI-D, and I would like to run both monitors together. It's wierd, when I boot up the system, it starts with the VGA monitor and then switches to the DVI monitor, but if the VGA isn't connected, it wont go to the other. The point is, I know they both work, just not at the same time. Does this card simply not support dual displays?

Anyone?

Bueller?

  • 3 Contributors
  • 2 Replies
  • 102 Views
  • 1 Month Discussion Span
  • Latest Post Latest Post by dogswallower

Dani AI

Generated

This looks like the classic single-head vs. multi-head question. Before buying anything, confirm what the Mac actually reports: open Apple System Profiler (or System Information) and look under Graphics/Displays. Copy the graphics section here if you want help interpreting it. That output tells whether the installed adapter exposes one framebuffer (single-output) or multiple independent displays.

As suggested, swapping or adding a card is the normal fix. Two practical routes:

  • Install a second PCI video card. Under Mac OS X the system will detect the extra card and give a second independent desktop. Note: the secondary card usually will not show the startup/firmware screen — only the primary/boot card will — and driver support matters (OS X vs. OS 9).
  • Replace the existing AGP card with a true dual-head AGP card that advertises two independent outputs. That preserves a single framebuffer and will behave like one large/continuous desktop for apps that expect a single display.

A few caveats to keep in mind for choosing hardware: pick cards with native Mac drivers for your OS version, check that the card fits the Sawtooth’s slots, and expect that mixing different vendors can sometimes limit hardware acceleration on one display. Also decide whether you need an extended desktop (separate screens, normal for productivity) or true spanning (one contiguous framebuffer for certain fullscreen apps); true spanning usually requires a single dual-head card or a special spanning adapter.

To move forward: post the System Profiler graphics section, state which Mac OS version you run, and whether you need full-screen spanning or just two independent desktops. That will make a specific card recommendation and install checklist possible.

Recommended Answers

All 2 Replies

Member Avatar for yellow

Does this card simply not support dual displays?

You've found the source of your own problem. The solution? A new Video card to replace your internal, or a PCI version of the same to use as the source for a second monitor.

Member Avatar for dogswallower

You've found the source of your own problem. The solution? A new Video card to replace your internal, or a PCI version of the same to use as the source for a second monitor.

I'm having a similar problem with my G4. So the ATI ragePro 128 doesn't support dual display? Wish I'd known that before I bought the DVI/VGA adapter. Ah well. Does anyone know from firsthand experience if simply adding a second PCI card will allow me to run in monitor-spanning mode. Or do I need one card to run both displays?

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.