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Cube making ADC display go black
Posted by: eharmon on 2026-08-05 18:40:39 I've got a 22" ADC display connected to a cube. At boot, it works fine, but once the OS loads (9 or X), the screen goes blank with the backlight off. 9 goes black immediately, X after spinning the wheel for awhile, presumably once the display driver loads. It's almost like they're both configuring a resolution the display doesn't support. The system keeps running, you just can't see anything. Things I've tried: Using the ADC display with a DVI converter on a Mac mini -- works fine Using the Cube with a VGA display -- works fine Replacing the PRAM battery, which was dead -- no improvement Resetting the PRAM -- no improvement So it seems like the display works fine, the Cube outputs video fine, and the Cube saves PRAM settings fine. But put them together and it goes black every boot (and comes back every reset until the OS takes over). In other words, OF can display to the screen, but no OS can. The Cube is running the Rage 128 Pro. Any ideas?
Posted by: Durosity on 2026-08-05 22:57:08 Are you sure it’s the 22” Cinema Display and not the 23” one? The 128 pro can drive the 22 but not the 23..
Posted by: chriscarruthers on 2026-08-05 23:24:40 Yep 32MB+ VRAM required.
Posted by: eharmon on 2026-08-09 20:39:49 Thanks for looking. Seems like I got it wrong, but in a way that isn't commonly cited: it's actually a 20" Cinema Display, which is 1680x1050 and requires 32MB of VRAM as well, unlike the 22 which was only 1600x1024. I've always heard a 23" won't work, but a 20" won't work either! Annoying neither OS falls back to the supported 1280x800 instead... Now I need to hunt for a GeForce...
Posted by: chriscarruthers on 2026-08-09 20:51:47 Makes sense. I've got a 20" too and ran into the same problem. I found the GeForce2 MX uncomfortably warm in the Cube TBH. The Radeon 7500 is MUCH cooler, faster, and fits... just without the stock faceplate unfortunately.
Posted by: eharmon on 2026-08-09 21:07:42 Makes sense. I've got a 20" too and ran into the same problem. I found the GeForce2 MX uncomfortably warm in the Cube TBH. The Radeon 7500 is MUCH cooler, faster, and fits... just without the stock faceplate unfortunately. Yeah, I guess the proper cube version ran with a fan. I found the standard one without for $35 which...good enough for short-term usage, at that price. No 7500s with ADC on eBay so I'll keep hunting (though I do have the DVI->ADC if I have to, but the old cube owners table indicates you can't flash PC cards?)
Posted by: chriscarruthers on 2026-08-10 04:53:44 Yeah I believe the GeForce2 MX in the Cube perhaps meant to ship with a fan but actually ended up with a really large heatsink instead? I've never seen a photo of either and the info online is hard to trust. I'd love to hear from anyone who's got first-hand knowledge. Good luck anyway!
Posted by: François on 2026-08-10 14:55:20 I had a GeForce 2MX in my Cube (bought new 25 years ago!) and it had a big heatsink.
Posted by: eharmon on 2026-08-10 16:21:50 I wouldn't call this one large, so if the Cube just shipped with a big one maybe I'll just swap it.
Posted by: chriscarruthers on 2026-08-10 18:11:06 Yeah that’s the standard one as shipped in the towers. Needs more airflow than it gets in the Cube.
Posted by: chriscarruthers on 2026-08-14 19:19:53 Apparently this is it? https://web.archive.org/web/2006102...ery/video_card_visuals/GF2MX_CubeOEM_Heatsink
Posted by: eharmon on 2026-08-14 19:25:47 Apparently this is it? View attachment 102652 https://web.archive.org/web/2006102...ery/video_card_visuals/GF2MX_CubeOEM_Heatsink Nice find, definitely beefier. Looks pasted on the memory chips as well. I'll approximate some measurements based on the real card, but at a glance I bet one of these is close: https://www.amazon.com/Aluminum-Heatsink-100x60x10mm-Conductive-Smartphones/dp/B0CMSVL782/
Posted by: eharmon on 2026-08-14 20:41:55 The GeForce really does run hot, I'm surprised I don't see heat marks on this one from running in a tower, honestly. Looks more like a 70x70 heat sink is right. I'll do some experiments and start a new thread!
Posted by: François on 2026-08-15 15:44:41 Apparently this is it? View attachment 102652 https://web.archive.org/web/2006102...ery/video_card_visuals/GF2MX_CubeOEM_Heatsink This is the one that shipped with the Cube. IIRC a lot of them failed because they were running so hot!
Posted by: eharmon on 2026-08-26 23:29:22 Interestingly my card had firmware 125, which was replaced by at least one newer version in Display Software 2.1.1 which included 136. That disc was, I think, included with the Cinema Displays. I wonder if it makes the card at least display at lower resolutions instead of going blank.
Posted by: Coloruser on 2026-08-27 01:40:39 No Firmware magic will make the Cube´s Rage 128 work with the 20” Cinema Display. The Display itself has no Scaler - thus support of the resolution of 1680x1050 is needed. I went thru this last year. As mentioned above, the only way is a 7500 or a 2MX with ADC. VRAM is by the way not the limitation, it´s the Rage 128´s TMDS receiver/transceiver that is not suited for a higher resolution. DVI was in its infancy when the cube came out and the original Rage 128 (Orion) had only VGA. The card does not support the full 165Mhz TMDS bandwidth (which would be good enough for 1920x1200 with reduced blanking) but only roughly 136Mhz, while 146Mhz would be needed for 1680x1050.
Posted by: indibil on 2026-08-27 02:03:36 Hi, I installed a GeForce2 32MB in a Cube. It came from a QuickSilver and I noticed it got hot. Larger, passive heatsinks could be used, but I removed the original one with a air heater and added one like this: Heatsink I seem to recall connecting it to 5V (very quiet), and the bracket is also interchangeable with the Cube's Rage Pro. In another Cube, I installed a Radeon 9250 low profile with the heatsink from an Nvidia FX5600, which is as large as the original GF2 heatsink from the Cube, but with a fan. It seems that back then, the holes in all the heatsinks were the same.
Posted by: eharmon on 2026-08-27 16:58:36 No Firmware magic will make the Cube´s Rage 128 work with the 20” Cinema Display. The Display itself has no Scaler - thus support of the resolution of 1680x1050 is needed. I went thru this last year. As mentioned above, the only way is a 7500 or a 2MX with ADC. VRAM is by the way not the limitation, it´s the Rage 128´s TMDS receiver/transceiver that is not suited for a higher resolution. DVI was in its infancy when the cube came out and the original Rage 128 (Orion) had only VGA. The card does not support the full 165Mhz TMDS bandwidth (which would be good enough for 1920x1200 with reduced blanking) but only roughly 136Mhz, while 146Mhz would be needed for 1680x1050. Well, what has me curious is that doesn't quite add up: before the screen goes blank, the 20" is displaying full screen (stretched, or native) content from the Rage. So, if the Rage is scaling it's successfully outputting 1680x1050, albeit possibly at lower bit-depth. Which should be impossible...
Posted by: Coloruser on 2026-08-28 00:32:30 Well, what has me curious is that doesn't quite add up: before the screen goes blank, the 20" is displaying full screen (stretched, or native) content from the Rage. So, if the Rage is scaling it's successfully outputting 1680x1050, albeit possibly at lower bit-depth. Which should be impossible... That´s the standard behavior. On Startup, a lower resolution is used by Mac OS but as soon as the OS and the Card negotiate about the native resolution (that the display requests per its DDC EDID), the Cinema Display goes black as the Rage cannot drive 1680x1050. I have used a G4 to check the DDC EDID with a PCI Rage 128 in addition as the main display. If the ADC Rage is set to a scaled resolution, the Display shows up. But as soon as you restart, the display goes black again. I even disabled (covered) the DDC pins but that made the display go black right from the start. There are only two ways to solve this: use another graphics card or make the OS think, the display requests a lower resolution by some DDC hacking. On the PC driver of the Rage 128, you can set a reduced blanking which frees up some bandwidth. Some later ATI chips for the Mac also used that trick to get 1920x1200 displayed as their TMDS setup also doesn’t fully support 165Mhz. However, I have never found a way for the Rage 128 to enable reduced blanking permanently. Educated guess: Apple/ATI obviously implemented reduced blanking to make sure the ALU DVI Cinema Display can be driven by those cards. As the Rage doesn’t support 1920x1200, Apple/ATI never implemented that for this card. I have worked in the display industry in the early 2000s and that was quite a tough time to qualify and test display/card combinations as DVI implementations were pretty wacky in the early days of DVI.
Posted by: eharmon on 2026-08-29 12:49:52 That´s the standard behavior. On Startup, a lower resolution is used by Mac OS but as soon as the OS and the Card negotiate about the native resolution (that the display requests per its DDC EDID), the Cinema Display goes black as the Rage cannot drive 1680x1050. I have used a G4 to check the DDC EDID with a PCI Rage 128 in addition as the main display. If the ADC Rage is set to a scaled resolution, the Display shows up. But as soon as you restart, the display goes black again. I even disabled (covered) the DDC pins but that made the display go black right from the start. There are only two ways to solve this: use another graphics card or make the OS think, the display requests a lower resolution by some DDC hacking. On the PC driver of the Rage 128, you can set a reduced blanking which frees up some bandwidth. Some later ATI chips for the Mac also used that trick to get 1920x1200 displayed as their TMDS setup also doesn’t fully support 165Mhz. However, I have never found a way for the Rage 128 to enable reduced blanking permanently. Educated guess: Apple/ATI obviously implemented reduced blanking to make sure the ALU DVI Cinema Display can be driven by those cards. As the Rage doesn’t support 1920x1200, Apple/ATI never implemented that for this card. I have worked in the display industry in the early 2000s and that was quite a tough time to qualify and test display/card combinations as DVI implementations were pretty wacky in the early days of DVI. Yeah, I get the fundamental Rage limitation. What's interesting is since the Cinema is displaying edge to edge, it's either scaling or the Rage is successfully driving 1680x1050 (not frame buffer, but in the TDMS) while it's in OF/BootX. Which is curious. Which makes me wonder if it starts in reduced blanking, yeah, or the display has some level of scaling (maybe only pure integer and not arbitrary?)
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