Some bugs will happen because some people have odd old computer components. When I migrated the contents of my 2018 MacMini running Sonora to my band new 2024 MacMini running Sequoia I hooked the 2024 MacMini to an old DVI display through a HDMI to DVI adapter because I only had one HDMI display at hand. The 2024 mini ran on the old DVI display for the initial boot but would not display anything on the DVI screen after the migration. It only ran properly when I connected the 2024 mini to the HDMI display the next day. Initially I saw it as a serious bug, but once it worked on the HDMI display, I realized the problem was trying to use the DVI screen that must be over a decade old. It had always worked before, and it was only a backup, so I never saw a reason to replace it.
I took the 2024 Mini to the Apple Store and I already ordered a cheap HMDI-DVI cable from eBay, where the tech who seemed to be specialized in hardware got it going using my HMDI cable and an Apple disply and keyboard. I was pleasantly surprised to see the migration had gone through cleanly. He thought the problem probably was the DMI adapter or the display. I didn’t have any others around the house, but at $7 from ebay it seemed worth checking.
EBay delivered the new HDMI/DVI adapter surprisingly quick, and I just plugged it into the 2018 MacMini and and the old 22-inch DVI monitor. Nothing happened. Had the screen decided to die in the middle of the migration? I plugged in my 2004 PowerMac G5, in a DVI cable from for G5 to the DVI Port and the G5 display booted up on the DVI monitor. So the screen works. Then I hooked a HDMI cable from the HDMI port on the 2018 MacMini to my 27-inch Dell HDMI screen, and after a little while, the 2018 Mini display booted on the 27-inch screen with a HDMI port. So the 2018 mini is still alive and operational. Both of the HDMI/DMI adapters don’t work. Both are no-name models, but I assume the old one must have worked at some point or I would have tossed it. The new one was in what looked like a factory-sealed bag from China. The two HDMI/DVI adapters look very similar, so it’s possible they came from the same source in China, so maybe they both came from the same bad lot or crummy factory. Or it’s possible I never used the old display with the 2018 Mini; I had to replace a dead 27-inch monitor in November 2022, so the 22-inch DVI may have been left over from a 2010 Mini that has been recycled.
So conclusion is not to expect 2024 Mini to run with displays that lack HDMI ports; you probably need HDMI to HDMI.
Except that my experience has been exact opposite. My Dell DVI display is connected to a 2024 mini’s HDMI port using an Apple HDMI-DVI adapter (the one that was bundled with my 2011 mini and is, sadly, no longer being made).
So, my conclusion that the problem is one of:
- That cheap adapter is not compatible
- Your display’s DVI interface is particularly sensitive to subtle issues with the signal (which my display is OK with)
Since you’ve already found a solution (use a display with an HDMI port), I wouldn’t bother trying to spend more money on the problem, but my next step here would probably be to use a USB-C-DVI adapter/cable.
It is very strange that it initially worked and then failed after migration. Which seems to indicate that some system configuration is putting out a signal the display can’t handle. An interesting test might be to set up screen sharing, then switch back to the DVI display and connect to the screen from another computer. From there, open the Displays settings page and see if any of the available resolutions work.
For all I know, macOS is auto-detecting a frequency that the display can’t handle and is setting that mode. So manually setting something that you know to be compatible may be the fix (and would provide enough information to file a good bug report with Apple).
For both my 2020 M1 Mac Mini, and my 2024 M4 Mac Mini (traded the M1 in for the M4), I have a Samsung 24" monitor, and the HDMI cable worked fine for the M1, and works well with the M4. I assume it will be the same with Tahoe.
Thinking back to what the Apple Store tech said, I don’t think Apple tries to make their new Macs compatible with older interfaces, adapters, or screens. Sometimes Apple may warn that some old features won’t work, but in this case Apple’s video output was in the well-established HDMI format, not anything exotic.
What I had forgotten was that the old 22-inch Samsung DVI monitor dated way back to 2008, and was used originally on my 2004 G5 PowerMac and then with my 2010 Mini. By the time I bought the 2018 Mini, I had already switched to a 27-inch monitor and put the 22 inch on a shelf. However, that first 27-inch monitor that failed in 2022, and I replaced it with a Dell 27-inch HDMI monitor that I was used on the 2018 Mini. I left 27-inch Dell attached to the 2018 mini for migration because it seemed simpler than reconnecting everything before migration, and attached to it to the old Samsung DVI, which did boot up and perform the initial stages of setting up the 2024 mini and migration. That fooled me into thinking the 2024 mini would be able to boot on the old Samsung DVI monitor once I had migrated my data.
When I tried to reach Apple Support, it told me that only Chat was available, so I signed up for the chat on my working 2018 Mini using the 27-inch Dell HDMI screen. That was my only choice because the 2024 mini would not boot only the older 22-inch screen, but it was inadequate to handle the problem because I didn’t have a way to switch screens to test other configurations.
The tech on the Chat did not mention any input diagnostic data Apple was getting from the 2024 or 2018 minis, so I assume assume they were getting nothing. Once I got to the Apple Store the next day, the tech tech was able to get the 2024 Mini up and running easily and helped me complete initial setup.
But this isn’t anything exotic. In fact, HDMI is a superset of single-link DVI. The two are electrically compatible for all single-link DVI resolutions (basically, up to 1200p at 60 Hz). The only significant differences between the two, at those resolutions are:
- No audio over DVI
- RGB-only (HDMI also supports YCbCr color-spaces)
- DVI displays report different plug-and-play data via the EDID data block
If you try to drive an HDMI port at resolutions higher than what single-link DVI can support (resolutions that are supposed to require dual-link), your display may reject it. The Mac may not realize this if macOS is assuming that the display will be actual HDMI.
What is its native resolution? If you don’t know, can you share its model number? If it was used with a G5, it may require dual-link DVI in order to get its native resolution. This could easily be the cause of the problem.
I don’t know of any adapter to convert HDMI to dual-link DVI, but some searching did find USB-C (that is, DisplayPort) adapters, like this one. Note that these cost quite a bit more because they are active adapters - they need a frame buffer to receive the HDMI data and transmit different parts of the frame on the two links. They will likely also increase latency (probably only noticeable when watching movies or gaming).
With a passive adapter, you’ll be limited to single-link DVI resolutions, which might be less than the display’s native resolution. If this is the case, then my hack of remote-login so you can select a lower resolution may work. At least to get an image on the screen, even though it will be lower resolution than you will want.
Thanks. That explains a lot. The USB-C Display Port adapter you shows has the same layout of pins as the ones labelled “HDTV/DVI” that I bought. That also is the same pin layout in the 2008 Samsung monitor and used in my 2004 PowerMac G5. It’s listed as a DVI-D Dual Link in this chart (Digital Visual Interface - Wikipedia) The cable that works between the Samsung monitor and the G5 has DVI-D dual link connectors on both ends. I had not realized there was any operational difference because it had worked previously. This teaches me I need to look more carefully at cables and watch carefully for details before buying them, although that’s getting harder as connectors shrink and my aging eyes get older.
The 22-inch monitor is a SAMSUNG SychMaster 220WM and the manual says “22 inch Wide (55.9 cm) - 1680 X 1050” resolution. I don’t know what resolutions are possible with the 2018 Mini, but that’s not an option on my 2024 mini. However, my top priority now is to catch up on on work.
Thanks very much for the education on connectors and displays.
- Jeff
Dual-link and single-link adapters will have the same number of pins in the female connector, and may have the same number in a male connector as well, even if only half are used.
Thanks. That means it should work fine with single-link DVI (the maximum is something around 1200p - 1920x1200, and this resolution is less along both axes).
I would be surprised if the 2024 mini can’t put out that resolution. Most GPUs (including, I would like to assume, Apple’s) can put out any resolution within the frequency limits (dot-clock, horizontal refresh and vertical refresh) of the signal generator.
So yes there’s something weird going on. The Mac is either not putting out a signal (can’t auto-detect the right resolution?) or it is putting out a signal the monitor can’t display. But after reading through the monitor’s manual, you should get an error on-screen if it receives an incompatible signal.
Knowing all this, I wouldn’t spend another penny on adapters, and I suspect experimenting enough to determine a cause will probably take a lot of time for no good reason, since you’ve already swapped out the monitor for a compatible one.
I’ve come to the same conclusion; any more fiddling with the old Samsung monitor and will be a waste of time. My 2004 PowerMac G5 is the only machine in the house that can communicate with the Samsung, and everything on the G5 has been transferred to the 2018 and 2024 Minis. I’ve learned some lessons, but it’s not worth any more time or money fooling around with the adapters.
Thanks, Jeff