Power Macintosh G3 with Dual Hi-Res Monitors

Question

Level 1

4 points

Power Macintosh G3 with Dual Hi-Res Monitors

Hopefully, this info will help someone wanting to run large dual flat-screen monitors (4:3) on Power Macintosh G3 Beige Minitower. My results stemmed from a previous post that I started, which was “DVI PCI Card/s for G3 Minitower”, but everything ended up such that I felt the need for a new subject header.

It appeared that no one had actually done what I was trying to do, so there was no guarantee it was possible. However, several of you gave some great suggestions to try, and between y’all’s help and a lot more reading and experimenting, I “cracked the nut”.

So, I wanted to report back here as to how it all worked out, so that anyone desiring to run two modern flatscreen monitors at 1600 x 1200 resolution on a G3 Beige Minitower could do so, and without having to go through what I had to. I would imagine this would apply to the the desktop version as well, but not sure.

The first thing to know is that, according to the apple specs, the machine HAS to have the 333 MHz motherboard, as anything less will NOT support above 1280 resolution.

Secondly, I could never get two monitors attached to both VGA cards (I had two of them in the PCI slots). It was suggested I zap the PRAM, but that didn’t allow it to work.

So, by using the factory DB15 video port as Monitor 1, I had to have an adapter to VGA. I tried 3 different Mac to VGA adptrs., and no matter how I set the dip-switches, it wouldn’t work. All of a sudden something dawned on me. If the G3 (333 MHz) would support 1600, and the monitor would support 1600, why do we need switches. Just adapt the fitting.

So, I purchased a DB15 to VGA straight adpt. with no switches just to adapt the cable connection to VGA. Here’s the interesting thing. After I booted, and got to the desktop, my RH monitor (attached to the VGA PCI card) was at 1600, but the LH monitor was NOT set to 1600. So, I went to the monitors CP to see if it showed as being available. It WAS there, but in italics, which normally means not available. Just for grins & giggles, I decided to click on it anyway, and when I did, a window came up stating that I had elected to change screen resolutions, and to confirm my choice. What to lose, right? So, I clicked OK, and, lo & behold, it changed to 1600 x 1200. Now, both screens are at 1600 x 1200 every time I boot up. I was blown away. Incidentally, the monitors I chose were fantastic . . . Dell UltraSharp 2007FPb (4:3 Ratio).

If this helps just one person, I’ll be happy.

Tom

PowerMac

Posted on Aug 12, 2016 5:48 PM

Reply

Answer 1

BDAqua

Level 10

250,259 points

Aug 12, 2016 8:37 PM in response to RedBullX90

Great work Tom, thanks for the report, I wondered what happened. 🙂

Reply

Answer 2

RedBullX90 Author

Level 1

4 points

Aug 12, 2016 8:50 PM in response to BDAqua

Thank you.

Reply

Answer 3

Aug 16, 2016 12:31 PM in response to RedBullX90

a cool feature with that setup is that you can have two separate background images on each monitor on the extended desktop. Makes a nice panoramic backdrop.

So which PCI VGA card were you using? Do you think it was the power draw of two PCI cards causing them to not work, but one single card works? I used a Samsung SyncMaster 204B with my G3 along with a 172N for a while, it was nice to have the extended displays, but I was able to drive both of them with a single dual-head PCI DVI/VGA card, ATI 9200.

Reply

Answer 4

BDAqua

Level 10

250,259 points

Aug 16, 2016 6:03 PM in response to BDAqua

.

Reply

Answer 5

BDAqua

Level 10

250,259 points

Aug 16, 2016 6:05 PM in response to Glen Doggett

I think you very well may have it with the power issue Glen, thanks! 🙂

Reply

Answer 6

RedBullX90 Author

Level 1

4 points

Aug 18, 2016 12:39 PM in response to Glen Doggett

Hi Glen,

I never could find a dual port card that I was certain would work with that machine. The individual cards I was using were both Apple 630-2858, ATI 109-57400-00 Rage 16MB. I don't really know if the power draw was the issue, but I don't think so. When I tried to boot, a System Error occurred: "ATI Graphics Accelerator illegal instruction. To Temporarily turn off extensions, restart & hold down Shift Key".

So, I started up with Ext. off, and unit got to the desktop. Both monitors were working fine, but with low resolution, and, of course, no way to even attempt changing it, as the Monitors CP was disabled.

I don't know if I could've done it with one dual-port card, but first, I could find very few dual-port VGA cards for the Mac, & was confused as to which ones would work in the G3 Minitowers. Also, don't forget, I was wanting 1600 x 1200 resolution.

I guess it really doesn't matter, as it's not really an inconvenience using the factory port w/adpt. for Mon.1, and I've achieved exactly what I started out to do. The trick was to use an adapter with no dip switches, since both the G3 (333MHz) and the monitor supported 1600 x 1200 resolution.

Thanks again for the input,

Tom

Reply

Answer 7

Aug 18, 2016 10:41 PM in response to RedBullX90

Yes, the compatible cards are very hard to find these days, and they probably cost more than the value of the machine now. A current search of eBay has two sellers with the PCI ATI Radeon 7000 Mac Edition card 64MB VRAM, not one of the best cards ever made for that vintage computer, but it is a dual-head. It can drive two VGA monitors if you use a DVI-VGA adapter on the DVI output port. With a dual-head card, you could also use the built-in video card to drive 3 monitors! In any case, glad to hear someone is still enjoying their G3, I got many years of use from my G3 Desktop a long while ago.

http://www.ebay.com/itm/ATi-Radeon-7000-64mb-PCI-Video-Card-For-Apple-PowerMac-G 3-G4-G5-Xserve-DVI-VGA-/261435567084?has…

http://www.ebay.com/itm/Apple-Mac-G4-G5-ATI-Radeon-7000-PCI-64MB-Video-Card-DVI- VGA-S-Video-TV-Out-OS9-/200710223413?hash=item2ebb42f635:m:mosu41F9PFEhHQf6EhSbd GA

Reply

Answer 8

RedBullX90 Author

Level 1

4 points

Dec 30, 2016 6:34 AM in response to RedBullX90

Hey gang . . . I have an update on this issue. I am interested in having a back-up unit for the one I created for the dual monitors @1600 x 1200 resolution.

I have run across an opportunity to purchase a 266MHz Beige Minitower that has been upgraded with a 500MHz processor. The system profile IS showing that the machine speed is, in fact, 500MHz, and the machine does have the 6MB VRAM, in case that matters.

Here's my question. Since Apple specifications claim that ONLY the 333MHz machine will support 1600 x 1200 resolution, I'm wondering if there would be anything else about the 333MHz machine that's important here, or does it have to do with the speed only, which would mean (?) that 333 OR FASTER would work. If it would, then I could buy the 266 machine that's upgraded to 500 as a backup.

I hope someone knows about this, and thanks for any help.

Tom

Reply

Answer 9

BDAqua

Level 10

250,259 points

Dec 30, 2016 9:21 AM in response to RedBullX90

What revision mortarboard is it?

https://www.macgurus.com/products/motherboards/mbppcg3desk.php

Reply

Answer 10

Jeff

Level 6

12,328 points

Dec 30, 2016 1:31 PM in response to RedBullX90

As I recall, the motherboard that shipped with the 333 MHz G3 desktop/mini-tower models had ATI's "Rage Pro Turbo" GPU. The previous motherboard had the "Rage Pro," and the first version had the "Rage II +DVD." This might account for the difference in supported resolution/refresh options.

Reply

Answer 11

RedBullX90 Author

Level 1

4 points

Dec 30, 2016 3:03 PM in response to BDAqua

Thanks for the reply.

All I know is it's a 266MHz unit with a 500MHz upgrade. It DOES have the 6MB VRAM.

Tom

Reply

Answer 12

BDAqua

Level 10

250,259 points

Dec 30, 2016 3:34 PM in response to Jeff

Thanks Jeff, I think that must be it.

Reply

Answer 13

RedBullX90 Author

Level 1

4 points

Dec 30, 2016 4:05 PM in response to Jeff

Hi Jeff,

Thanks for the reply. I'm not certain I'm reading you right, but if I am, the Minitower I'm looking at might not work.

Let me explain what I think I understand what you are saying means, and then you tell me if I'm correct:

Even though the 266MHz machine I'm looking at has had a 500MHz processor upgrade, it still (being a 266) would NOT have the "Rage Pro Turbo" GPU. What this would mean is that if the "Rage Pro Turbo" GPU has anything at all to do with the 1600 x 1200 resolution support, then just the fact of it being 500MHz processor speed wouldn't matter.

If this is correct, then I should NOT but the computer, and just keep looking for another factory 333MHz unit.

Tom

Reply

Answer 14

BDAqua

Level 10

250,259 points

Dec 30, 2016 11:53 PM in response to RedBullX90

In February 1998, ATI introduced the 2x AGP version of the Rage Pro to the OEM market and attempted to reinvent the Rage Pro for the retail market, by simultaneously renaming the chip to Rage Pro Turbo...

https://en.wikipedia.org/wiki/ATI_Rage

Video Card:

3D Rage II+*

VRAM Type:

EDO SGRAM

Details:

*ATI 3D Rage II+ graphics onboard originally, upgraded to ATI Rage Pro starting May 1, 1998. The M6142LL/A configuration also has 8 MB of VRAM on a 2D/3D graphics PCI card.

Standard VRAM:

2 MB, 6 MB*

Maximum VRAM:

6 MB*

Display Support:

Single Display*

Resolution Support:

1024x768*

http://www.everymac.com/systems/apple/powermac_g3/specs/powermac_g3_266_mt.html

Video Card:

Rage Pro Turbo

VRAM Type:

EDO SGRAM

Details:

*ATI Rage Pro Turbo graphics with 6 MB of VRAM.

Standard VRAM:

6 MB*

Maximum VRAM:

6 MB*

Display Support:

Single Display

Resolution Support:

1600x1200*

http://www.everymac.com/systems/apple/powermac_g3/specs/powermac_g3_333_mt.html

Reply

Answer 15

RedBullX90 Author

Level 1

4 points

Dec 31, 2016 3:33 PM in response to BDAqua

Thanks so much for those great references. I've got a folder I can save those in.

Happy New Year, and prayers for no serious incidences.

Reply