G4 PPC Towers with Modern Monitors Adapter

joevt

Tinkerer
Mar 5, 2023
73
32
18
But for best results, you want to keep the signal digital. Don't all/most G4 towers have DVI output? That's equivalent to HDMI up to 165 MHz (HDMI 1.1 ≈ 1920x1200@60Hz). You just need a passive DVI to HDMI adapter for that. Beyond that you're dealing with Dual Link DVI (up to 330 MHz) which will require a Dual Link DVI to DisplayPort adapter. This is near HDMI 1.4 bandwidth (340 MHz) and can do 2560x1600@60Hz or 4K 30Hz.

I don't think the DVI outputs of Power Macs include audio, so you would need some kind of HDMI audio embedder or inserter to get analog audio to a display that supports audio.
 

Slimes

Tinkerer
Jul 26, 2023
29
25
13
Canada
www.slimes.ca
Apparently there are pixel clock limitations which keep the resolution lower than what a VGA signal can provide. Good example is the Mac Mini G4.


"This 135 MHz pixel clock limit for non-coherent displays only applies to DVI; VGA has higher limits (pretty much necessarily, because CRT monitors require more blanking which drives up the required pixel clock for a given mode). I've been able to drive 2560×1024 at 60 Hz from my G4 mini's VGA output. According to my calculator, that's a pixel clock of 218 MHz using CVT or GTF timings. For that matter, I've also been able to drive 3840×2400 at 13 Hz from my G4 mini's DVI output but that's only a 125 MHz pixel clock using CVT-RB timings and thus, safely within the mini's limit."

I also found that a DVI-D to Vga Adapter simply didn't work, and a DVI-D to HDMI adapter left me with a black screen after boot. After using a DVI-A to VGA adapter everything worked.

I experienced the same with DVI out on PowerMac G4 towers.
 
  • Like
Reactions: joevt

S. Pupp

New Tinkerer
Apr 2, 2023
60
21
8
I use something similar for the same reason - I can get 1080p via a VGA-HDMI adapter, which is unobtainable via my MDD G4’s DVI.
 

Certificate of Excellence

Active Tinkerer
Nov 1, 2021
687
482
63
47
United Sates
The early Powermac G4s I have include either TNT Pro or Geforce MMX 2 & 4, all of which include VGA and ADC, but no DVI. DVI started showing up at MDD and their Radeon 9000s. I was considering this cheap adapter as a solution for my Blue & White actually which has only VGA out at the moment. This would help with connecting it to a broader range of displays.
 
  • Like
Reactions: KingDingus

Slimes

Tinkerer
Jul 26, 2023
29
25
13
Canada
www.slimes.ca
I tested the device on my B&W G3 Tower. Works good.

Anyone know where to find a ADP (Apple's round DVI knockoff) to DVI Adapter? I used to have one, but lost it. The digital to vga signal seems to center the screen better than straight VGA.
 

Certificate of Excellence

Active Tinkerer
Nov 1, 2021
687
482
63
47
United Sates
I tested the device on my B&W G3 Tower. Works good.

Anyone know where to find a ADP (Apple's round DVI knockoff) to DVI Adapter? I used to have one, but lost it. The digital to vga signal seems to center the screen better than straight VGA.
Those adapters are the A1006. I have collected a few over the years. You can find them on ebay pretty regularly however they're pricey. Ive found a few on shopgoodwill.com for better prices however the best pricing is if you can find bundled with an old screen - for example I got another for free effectively bundled with a 22" acrylic Apple Cinema DIsplay purchase on Craigslist.