I Need Help Getting A Video Signal To My G4 MDD Using An ATX Power Supply.

2112st

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Oct 8, 2023
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This is an off-shoot from this thread:


The G4 MDD is hooked up to my 32-inch Panasonic Viera TV (2010). My 2010 Mac Mini is hooked up to it as well. Note the connections in the back. The Mini is using the HDMI connection, and the G4 the VGA. When I installed the new power supply, I got the start-up bong, but no video signal. I reinstalled the old power supply for the time being, and I'm getting a video signal again.

The question now is-how can I make a video signal to the TV work, using the new power supply? Will this mean getting a different video card or external device? This is new territory for me, so any help is welcome. :)


Panasonic Viera.jpg Panasonic Viera-Rear Video Connections.jpg Video connector.jpg video card.jpg Power Supply.jpg New PS & Adapter.jpg
 
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ClassicHasClass

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I can't tell from your picture: is that an ADC or a DVI connection? What connectors are on your card? If it has a DVI or VGA port, any difference?

The power supply provides the ADC voltage, which you'd need to convert from ATX (the ATX-to-G4 converters I've seen and that you appear to have are just passive connectors), or you swap the video card for something without ADC.
 
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2112st

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Oct 8, 2023
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Northeastern New Jersey, USA
I can't tell from your picture: is that an ADC or a DVI connection? What connectors are on your card? If it has a DVI or VGA port, any difference?

The power supply provides the ADC voltage, which you'd need to convert from ATX (the ATX-to-G4 converters I've seen and that you appear to have are just passive connectors), or you swap the video card for something without ADC.
Here you go. Forgive my ignorance; I don't know what the connections are called.

V1.jpg V2.jpg
 

ClassicHasClass

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No, actually, the one on the left is ADC, the one on the right is DVI. That looks like an ATI Radeon 9000 PRO. The ADC voltage is provided by that extra little set of "fingers" next to the AGP connector. I would think it would work without ADC voltage on the DVI port, but I've never tried.

Alternatively, you could get one of the Mac cards that doesn't have ADC, or (more difficult, haven't done this myself) tape and flash a PC AGP card.
 
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2112st

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No, actually, the one on the left is ADC, the one on the right is DVI. That looks like an ATI Radeon 9000 PRO. The ADC voltage is provided by that extra little set of "fingers" next to the AGP connector. I would think it would work without ADC voltage on the DVI port, but I've never tried.

Alternatively, you could get one of the Mac cards that doesn't have ADC, or (more difficult, haven't done this myself) tape and flash a PC AGP card.

That's where the problem lies. With the old power supply, the right video connection works. With the new power supply, it doesn't. I hear the boot-up bong, but no picture. At first, I thought the card was messed up, but when I put the old PS back in, everything worked again.

So-you say the solution is a new video card? What should I look for?
 

helmetguy

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Apr 1, 2024
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Did your MDD end up giving a video signal with the Geforce 2 from eBay and the ATX PSU? I'm curious as I'm one of the posters in the MRF thread linked earlier.

My ongoing assumption is that the Radeon 9000 is causing the "no video" issue with certain PSUs.
 
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2112st

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Oct 8, 2023
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Did your MDD end up giving a video signal with the Geforce 2 from eBay and the ATX PSU? I'm curious as I'm one of the posters in the MRF thread linked earlier.

My ongoing assumption is that the Radeon 9000 is causing the "no video" issue with certain PSUs.
LOL, I haven't ordered the card yet. I've been really busy. I hope to order it soon.
 
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2112st

Tinkerer
Oct 8, 2023
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Northeastern New Jersey, USA
Did your MDD end up giving a video signal with the Geforce 2 from eBay and the ATX PSU? I'm curious as I'm one of the posters in the MRF thread linked earlier.

My ongoing assumption is that the Radeon 9000 is causing the "no video" issue with certain PSUs.

Just contacted the seller. Will try and order this soon.
 

helmetguy

New Tinkerer
Apr 1, 2024
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Nice. Hopefully that gives you a working, quiet(ish) MDD.

I'm still trying to figure out why one of the ATX PSUs I tried in my MDD worked while the other two (one had better wattage ratings) didn't.
 
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2112st

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Oct 8, 2023
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Nice. Hopefully that gives you a working, quiet(ish) MDD.

I'm still trying to figure out why one of the ATX PSUs I tried in my MDD worked while the other two (one had better wattage ratings) didn't.
Action Retro's video was pretty useful. As I said-I did hear the start-up bong, just no picture. The old PS is temporarily back in the G4.
 

helmetguy

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Apr 1, 2024
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Admittedly I've never watched Action Retro's video, but I've now noted that he had the exact same issue - chime but no video - with his MDD's original video card and the same ATX PSU that you're using.

Aaaaaaaaaand no prizes for guessing what the original video card was:

Screenshot 2024-04-02 at 17.33.26.png


(a Radeon 9000)

I'm wondering why this issue hasn't come up more often with ATX PSU swaps in MDDs.
 
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2112st

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Oct 8, 2023
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Northeastern New Jersey, USA
Admittedly I've never watched Action Retro's video, but I've now noted that he had the exact same issue - chime but no video - with his MDD's original video card and the same ATX PSU that you're using.

Aaaaaaaaaand no prizes for guessing what the original video card was:

View attachment 15952

(a Radeon 9000)

I'm wondering why this issue hasn't come up more often with ATX PSU swaps in MDDs.
LOL, same card I have, apparently!

I just ordered the new video card. Let's hope it works with this power supply! :)
 
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helmetguy

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Apr 1, 2024
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I just realized that I have a number of old video cards that could potentially work with my own MDD, if flashed with a Mac ROM (they're all PC ROM video cards). So I dug out a Geforce2 MX and proceeded to flash it.

After ages of bashing my head against nvflash:

IMG_2497.jpeg


Finally, something went right with this cursed MDD :D

It successfully booted into OSX with a converted ATX PSU (one of my PSUs that wouldn't show video with a Radeon 9000) and Geforce2 MX. I used nvflash v4.42 and the OEM "revision 1100" ROM for the Geforce 2 MX from The Mac Elite.

I also have a Geforce3 Ti200 and Geforce4 MX to try, but they will need hardware modding AFAIK - the Geforce3 looks to need a resistor soldered to change its hardware ID, and all of my Geforce 4s are AGP 8x.

These aren't the greatest video cards for the G4 but my goal is to run OS9 on mine (it's a non-FW800 with the CPU board and heatsink from a FW800).
 

2112st

Tinkerer
Oct 8, 2023
257
98
28
Northeastern New Jersey, USA
I just realized that I have a number of old video cards that could potentially work with my own MDD, if flashed with a Mac ROM (they're all PC ROM video cards). So I dug out a Geforce2 MX and proceeded to flash it.

After ages of bashing my head against nvflash:

View attachment 15984

Finally, something went right with this cursed MDD :D

It successfully booted into OSX with a converted ATX PSU (one of my PSUs that wouldn't show video with a Radeon 9000) and Geforce2 MX. I used nvflash v4.42 and the OEM "revision 1100" ROM for the Geforce 2 MX from The Mac Elite.

I also have a Geforce3 Ti200 and Geforce4 MX to try, but they will need hardware modding AFAIK - the Geforce3 looks to need a resistor soldered to change its hardware ID, and all of my Geforce 4s are AGP 8x.

These aren't the greatest video cards for the G4 but my goal is to run OS9 on mine (it's a non-FW800 with the CPU board and heatsink from a FW800).

Today's my day off, so I've started the double-transplant (power supply & video card) now. I'll let you folks know how everything goes.