I have a 2011, 15" MacBook Pro (running 10.6.8) with the defunct, AMD(?) graphics chip. I'm trying to connect to a 23" Apple Cinema Display using a brand-new Mini DisplayPort to DVI adapter (LogiLink CV0037), **but it doesn't work.** I am aware that my laptop has a Thunderbolt port, not a Mini DisplayPort. However, everything I've read seems to indicate that a Mini DisplayPort to DVI adapter should work perfectly fine for what I'm trying to do, given Thunderbolt's 'backward compatibility'. The most likely culprit in my mind is that I've permanently disabled the faulty graphics chip by following these video instructions , which might be interacting with how my machine connects with the display. Is this likely correct? Is the AMD(?) chip required to run external displays? Are there any other obvious possibilities? Also, it's worth noting: Both the display and adapter do in fact work. I plugged the display into an older 17" MBP with a mini-DisplayPort with no problems. Also when I pull the adapter out of either the 15" or 17", the laptop screen goes blue for a few seconds, suggesting that the 15" MacBook Pro is also detecting something, just not integrating the display connection fully(?).

I'm setting up an old mac mini (specs below) with a dual boot (Ubuntu) and I've run into an issue getting to the Apple boot manager or the EFI boot manager. Essentially the monitor does not activate for either boot manager, however, if I wait or hit return straight away OSX loads, if I hit right and then return Ubuntu loads. So the boot manager is there but the screen simply isn't coming on yet. As soon as an os loads the monitor comes on and works just fine. The monitor is connected to the mac mini using a display port cable. The monitor works just fine on other computers with the same cable. I've tried a whole load of things: - reset PRAM or NVRAM and SMC - tried a different cable (display port adaptor to vga cable - so different port on the monitor) - did a fresh install of OSX (initially 10.6 and then updated to 10.8.5) - tried a different monitor (an old vga CRT) always the same. I'm now using the hdmi out of the mac mini (hdmi adaptor to dvi cable) and the monitor displays the boot manager as expected on boot up. So the problem seems to be either the display port on the mac mini (which doesn't make sense - it doesn't work and then it works once the os is loaded) or perhaps a display port driver (is the driver that specific?) incompatibility with the monitor (but it does the same with a different monitor) - neither really makes sense. Does the boot manager use its own drivers? Could they be corrupt (across fresh installs)? Is there something I'm missing here that I could try? -- Mac Mini mid 2010, 2.4Ghz Intel Core 2 Duo Nvidia GeForce 320m 256mb OSX 10.8.3

I’m trying to connect my M2 MacBook Air to a HP Compaq LA2205wg monitor which doesn’t support HDMI, which shows its age. I have resorted to buying a brand x USBC to DisplayPort adapter. Here's a photo of the connector: (https://media.cablematic.com/__sized__/images_1000/yp00200-03-thumbnail-1080x1080-70.jpg) I can’t get it to work. The MacBook isn’t aware of the monitor and the monitor says nothing’s connected. Is there a trick to making it work? __update__ I have tried connecting the same MacBook with the same adapter and the same cable to a different monitor. It worked, so I conclude that the monitor itself isn’t cooperating.

I have followed Apple's instruction in an attempt to use my old iMac as the second display monitor of my daughter's laptop with Windows 11(2024) for weeks....I would like to share my situation so I could get some expert insights on what else I could try. -My Imac is capable of this application- 27" late 2009 High Sierra 10.13.6 -Used Mini DisplayPort cable connecting Mini Display port(iMac) HDMI(PC). This cable should be working as we've been using to display imac screen to TV for years. -Both computers were rebooted and logged in as primary account holders in both systems. -Keyboard setting checked and verified command key is working Result: Imac; Command & F2 key should switch to " Target display mode" but this is not happening. The display shows no error message or error sound, no change on the screen. Window: I checked the multi-display setting, no other monitors can be detected. Many thanks! Hana

I have an Apple Macbook Pro 16 Inch (Touchbar) 2019 w/ AMD Radeon Pro 5300M. I'm running into issues connecting it to this monitor, [PX329](https://pixiogaming.com/products/px329) . If I use DisplayPort(this monitor supports up to version 1.2) then my mouse starts to lag/skip which is really annoying. If I use an HDMI cord, with [this](https://www.amazon.com/dp/B07THJGZ9Z) adapter, my external screen goes black about every 20-30 minutes for a second or two and then back to normal. I'm using 2560x1440 resolution on my external monitor w/ 50 Hertz refresh rate(I tried 60, same thing). At this point I'm not sure what I should buy. I'm considering either: 1. Get this [DisplayPort cable](https://www.amazon.com/DisplayPort-uni-Thunderbolt-Compatible-More-Gray/dp/B075V27G2R) or 2. Get an HDMI to USB-C cord without an adapter. Could you please recommend what's better, I'm not really sure what specs I should check on the monitor to figure out which route to go. Thanks so much.

I have a workplace setup for my Macbook Pro 15" (2011) that is actually two workplaces. One is the Macbook itself, for sitting. The second, right next to it, is a standing desk with an external monitor, keyboard, and mouse. This works great - I can work on the standing desk, and when my legs get tired, sit down for a while and continue seamlessly on the Macbook. The only painful point in the transition is that I have to physically disconnect the external display (an Acer 23" display connected through a MiniDP-to-HDMI cable) when sitting down, so the Macbook display becomes the main (and only) desktop again. Given that I may do this several times a day, this is bound to wear out the connector over time, something I'd like to avoid. Is there a more sustainable (software-only?) way to disconnect / deactivate an external display? All I can find on the Google is about the other way round (turning off the *internal* Macbook display).

I have a Macbook Air 2017. My goal is to have an optical output capable of 5.1 audio for my home theatre. My series of connections are, mini display port to hdmi and the hdmi connected towards hdmi to optical output and optical connected to my 5.1 home theatre. My midi setup and audio out setting automatically detected the hdmi out and and the hdmi icon appeared in both settings. But in my midi setup, it is showing 8 channels but, volume level of all of them is shown as disabled. All of the channel volume sliders are disabled. When I go for configuring, it shows 5.1 out. But when I tried to test each channels, only left and right are heard. All other channels are silent. When I played a 6 channel audio, it is missing every surround except from left & right. **I tried everything like soundflower, soundflowerbed app, MonitorControl etc. Nothing worked, still hearing only 2 channels.** **Is there any solution for this? I need a 6 channel audio output.**

Recently I purchased a 4K monitor for my Mac. I have a MiniDP to HDMI 2.0 converter and a HDMI 2.0 cable. I connected my late 2015 Retina iMac to the external monitor. I was able to get 4k@30hz on my external display. However, I was unable to achieve the 60hz refresh rate. After some research I figured that late 2015 iMacs with the thunderbolt 2 ports should support 4k@60hz video output. I can't seem to figure out why I can't get the 60 Hz refresh rate. When I open System Preferences, the Refresh Rate drop-down menu is gray. Mac Configuration: iMac (Retina 4K, 21.5-inch, Late 2015) MacOS: Catalina I connected the same monitor to my 2018 MacBook Pro using a USB-C to HDMI 2.0 cable. My MacBook Pro was able to drive the display at 4k@60hz.

I'm trying to connect a MacBook Pro 16" to my external display through DisplayPort with these devices : - Cable Matters Adaptater USB C to DisplayPort - DisplayPort Cable - External display : iiyama prolite b2783QSU But it's not working. When I plug it in, the external display goes out of sleeping mode, but the MBP does not detect it and after a couple of seconds, the display displays a "no input detected" message and goes back to sleep. I've tried : - Reseting the SMC and NVRAM and tried all 4 usb slots. - Switching off and unplugged the display, plugged it back in etc. - Restarting in clamshell - Force detect the display (the display goes out of sleeping mode, but then wont be detected) I've tested the cable, adapter and screen with another computer and everything works fine. Is there something I'm missing here ? Is it possible that my external display isn't compatible ? == **Edit** == It looks like incompatibility between MacOS and this iiyama model (or I guess this DisplayPort version). It also seems to be a software problem, since it works under Windows/Bootcamp (!) I've raised the issue to the Apple support, but of course no answer, and I think no hope of this getting solved. Basically, I need to buy a new screen... sad.

I have an M3 MacBook Pro and an M2 BackBook Air. I have been using my LG 27UL500 as a second display with the MPB for weeks and it has nice, dark blacks. I plug the Air into it with the same displayport cable and the everything is washed out and the blacks are gray. You can see in this image I took with my phone. Zoom in and see that the settings are the same, the resolution is the same, the refresh rate is the same and the color profile is the same. But here's what's *even weirder*--when you close the lid of the MBP *the external display becomes washed out too*! What could cause that?

I have a MacBook Pro (Retina, 15-inch, Mid 2014) , and I want to connect it to an ultra-wide monitor (3440 x 1440) . I'm using an HDMI cable and wonder if DP cable would work better. The monitor's resolution doesn't show up in the options in system settings -> displays, and the ones that are offered always result in a horizontally stretched image. So I installed SwitchResX , and created a custom resolution of 3440 x 1440, and applied it. This results in the top and bottom areas of the monitor being black, and the image in the center still stretched, and this seems to happen for all 21:9 resolutions. Side note: I've connected a PC to the monitor, both Windows and Ubuntu show the image correctly straight of the box, so I know the monitor works fine in principle using this HDMI cable and settings on the display itself. Is there any way I can work around this issue from macOS side?

Here are the specifications of the Apple M4 Mac mini: - Up to three displays: Two displays with up to 6K resolution at 60Hz over Thunderbolt and one display with up to 5K resolution at 60Hz over Thunderbolt or 4K resolution at 60Hz over HDMI - Up to two displays: One display with up to 5K resolution at 60Hz over Thunderbolt and one display with up to 8K resolution at 60Hz or 4K resolution at 240Hz over Thunderbolt or HDMI I have 4 displays, two of them are 2k 144hz, one 4k 144hz and one 4k 120hz, the specification text of the Mac mini only tells about 60hz and the resolution with it, but how about the higher refresh rate with resolutions? Is there a way to calculate if I can connect any combo of my displays?

I have an LG DualUp (28MQ780-B) display which I use with a MacBook Pro 14" (M2 Pro) over direct USB-C connection. Since updating to macOS Sequoia, the display no longer activates, though it will occasionally "thrash" between a single-display layout and the extended display layout, or if it is kept plugged in for an extended period of time, the system (display controller?) will eventually "partially" activate the extended desktop on a temporary basis. When this occurs, the extended desktop is visible in display settings and remote desktop, (and windows can be moved to it) but the physical display is still in sleep mode. If I touch the physical display's buttons to wake it during this state, the display disappears from the system immediately. I believe this to be a bug in macOS Sequoia since this update (from 14.current to 15.0.1) is the only variable between this part of my setup working or not. AppleCare is coming around, though not without first trying to convince me that USB-C or DisplayPort aren't actually "backwards compatible" in the way that we all know they are meant to be. Anyway, my question is what are the most likely root causes given an assessment of the following evidence: * The DualUp is an atypical display format; basically two 1440p displays stacked on top of one another (presented as one 2560x2880 display). * Using a CalDigit TS4 dock to provide my Mac with a full-size DisplayPort port, I can successfully drive either this DualUp display or a widescreen LG display of a different model (the alternate model does not have a USB-C interface). * The DualUp on Sequoia does not function over USB-C (DisplayPort over USB-C?), though it is recognized by the system as a USB device and provides USB-PD to the MacBook. * Troubleshooting steps taken to isolate the issue: powering the MBP via direct power adapter, restarting, switching user accounts to a standard test user, removing the CalDigit TS4 dock when testing the DualUp over USB-C, swapping the USB-C cable I usually use with the DualUp ($70 CableMatters 3m USB4) for the OEM included USB-C cable. Not tested (yet): safe boot, other host machines * When plugging in the DualUp via USB-C, I observe activity in Console.app from the WindowServer process including the message Failed to plug display -- sample included here:

00:09:20.735755-0400	WindowServer	Display 3 hot plug 1
default	00:09:20.735805-0400	WindowServer	IOMFBDisplay::update_power_state display_id=3 current_power_state=0 target_power_state=0 new_target_power_state=1 sync=0 raw_power_state=1 power_assertions=0
default	00:09:20.735837-0400	WindowServer	Display 3 set power state 1
default	00:09:20.736635-0400	WindowServer	 kern_CopyProperty key : VirtualDisplayMode not found
default	00:09:20.736694-0400	WindowServer	Display 3 uuid set
default	00:09:20.736731-0400	WindowServer	 kern_CopyProperty key : DisplayContainerID not found
default	00:09:20.738495-0400	WindowServer	Display 3 hotplug-state 1 updating digital modes: color 0x600001e0c9c0; timing 0x600001f5a1f0
default	00:09:20.738531-0400	WindowServer	Display 3 34 timing modes, 18 color modes
default	00:09:20.738934-0400	WindowServer	Display 3 current mode (0 x 0) [0 0], preferred mode (0 x 0) [0 0]
default	00:09:20.738990-0400	WindowServer	[ Display:Hotplug    ] Inserting hotplug event for state "in", display id: 3
default	00:09:20.739046-0400	WindowServer	[ Display:Hotplug    ] Processing hotplug "in" for display id: 3 (CA)
default	00:09:20.739145-0400	WindowServer	IOMFBDisplay::set_enabled=1
default	00:09:20.739265-0400	WindowServer	IOMFBDisplay::update_power_state display_id=3 current_power_state=0 target_power_state=1 new_target_power_state=1 sync=0 raw_power_state=1 power_assertions=0
default	00:09:20.739290-0400	WindowServer	IOMFBDisplay::set_enabled_ display_id=3, current_state=on
default	00:09:20.739414-0400	WindowServer	[ Display:Config     ] Display 3 failed to return any CA modes
default	00:09:20.739460-0400	WindowServer	IOMFBDisplay::set_enabled=0
default	00:09:20.747443-0400	WindowServer	IOMFBDisplay::update_power_state display_id=3 current_power_state=0 target_power_state=1 new_target_power_state=0 sync=0 raw_power_state=0 power_assertions=0
default	00:09:20.747484-0400	WindowServer	Display 3 set power state 0
default	00:09:20.747524-0400	WindowServer	 kern_CopyProperty key : Time not found
default	00:09:20.747982-0400	WindowServer	IOMFBDisplay::set_enabled_ display_id=3, current_state=off
error	00:09:20.748058-0400	WindowServer	Failed to plug display 3
default	00:09:20.748459-0400	WindowServer	[ Display:Power      ]   Work (D/C/W/S/P/R): 0/0/0/0/0/0
default	00:09:20.751070-0400	WindowServer	[ Display:Config     ] Detected match in persistent store.
default	00:09:20.751282-0400	WindowServer	[ Display:Config     ] Desired config set is valid.
default	00:09:20.751475-0400	WindowServer	[ Display:Config     ] No change between prior and requested configuration.
default	00:09:20.752139-0400	WindowServer	[ Display:Persist    ] Saving configuration: session, permanent store.
error	00:09:20.753386-0400	WindowServer	Source was stale because shmem was null: CFPrefsPlistSource (Domain: com.apple.windowserver.displays, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null), Contents Need Refresh: Yes)
default	00:09:20.755749-0400	WindowServer	Display 3 hot plug 0
default	00:09:20.755830-0400	WindowServer	 kern_CopyProperty key : DisplayAttributes not found
default	00:09:20.755857-0400	WindowServer	 kern_CopyProperty key : Transport not found
default	00:09:20.755888-0400	WindowServer	 kern_CopyProperty key : VirtualDisplayMode not found
default	00:09:20.755902-0400	WindowServer	Display 3  uuid cleared
default	00:09:20.755932-0400	WindowServer	 kern_CopyProperty key : IOMFBUUID not found
default	00:09:20.755951-0400	WindowServer	 kern_CopyProperty key : DisplayContainerID not found
default	00:09:20.756124-0400	WindowServer	Display 3 hotplug-state 0 updating digital modes: color 0x0; timing 0x0
default	00:09:20.756149-0400	WindowServer	Display 3 current mode (0 x 0) [0 0], preferred mode (0 x 0) [0 0]
default	00:09:20.756166-0400	WindowServer	[ Display:Hotplug    ] Inserting hotplug event for state "out", display id: 3
default	00:09:20.756194-0400	WindowServer	IOMFBDisplay::update_power_state display_id=3 current_power_state=0 target_power_state=0 new_target_power_state=0 sync=0 raw_power_state=0 power_assertions=0
error	00:09:20.757697-0400	WindowServer	Not updating lastKnownShmemState in CFPrefsPlistSource (Domain: com.apple.windowserver.displays, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null), Contents Need Refresh: Yes): 0 -> 548
default	00:09:20.757889-0400	WindowServer	[ Display:HDR ] Not populating capabilities for external display 3 set to sdr mode and brightness slider support is enabled.
default	00:09:20.757982-0400	WindowServer	[ Display:Hotplug    ] Processing hotplug "out" for display id: 3 (CA)
default	00:09:20.758143-0400	WindowServer	[ Display:Power      ]   Work (D/C/W/S/P/R): 0/0/0/0/0/0
default	00:09:20.758953-0400	WindowServer	[ Display:Config     ] Detected match in persistent store.
default	00:09:20.759052-0400	WindowServer	[ Display:Config     ] Desired config set is valid.
default	00:09:20.759128-0400	WindowServer	[ Display:Config     ] No change between prior and requested configuration.
default	00:09:20.759499-0400	WindowServer	[ Display:Persist    ] Saving configuration: session, permanent store.
error	00:09:20.760174-0400	WindowServer	Source was stale because shmem was null: CFPrefsPlistSource (Domain: com.apple.windowserver.displays, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null), Contents Need Refresh: Yes)
error	00:09:20.763209-0400	WindowServer	Not updating lastKnownShmemState in CFPrefsPlistSource (Domain: com.apple.windowserver.displays, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null), Contents Need Refresh: Yes): 0 -> 552
default	00:09:22.773394-0400	WindowServer	[0x13605e3a0] activating connection: mach=true listener=false peer=false name=com.apple.storagekitd.dm
default	00:09:22.790874-0400	WindowServer	[0x13605e3a0] invalidated because the current process cancelled the connection by calling xpc_connection_cancel()

My understanding of the interplay between Thunderbolt, USB-C, and DisplayPort is that it is complex to say the least. My best interpretation of the evidence is that we observe the TS4 dock doing a good job of demuxing a display signal to its DisplayPort port, and this makes for a much simpler connection to whatever display it is plugged in to. In contrast, when the DualUp is connected to the Mac via USB-C (directly or via a USB-C port on the TS4) the connection is doing double- or triple-duty as USB (for the DualUp's internal speakers and hub), USB-PD, and DisplayPort over USB-C. The macOS display controller tries to boot the display, and occasionally partially does so, but ultimately fails to coerce the physical display into activating. The conclusion I draw from this is that there are two possible root causes: 1. Less likely: the LG DualUp's USB-C implementation has a latent bug that was not evident under macOS 14, but is now causing an incompatibility with macOS 15. 2. More likely: macOS 15.0.1 has a software bug that is preventing the display controller from properly activating the DualUp over USB-C under these specific hardware conditions.

I own a: - **LG Ergo 34WN780** - Ultrawide QHD Monitor - 34 inch - **MacBook Pro** (15-inch, 2019) - **StarTech USB-C naar DisplayPort** cable 1,8 metres The monitor supports 75hz, but I can only configure it up to 60hz (3440x1440). I've also tried to use the cscreen utility from terminal, but if I set: cscreen -d 32 -x 3440 -y 1440 -r 75 -s 2 the monitor turns to 30hz for some reason, so it's decreasing (although I passed -r 75). What could be the issue? Update: I found this on some forum, by someone that bought my same exact monitor: if anyone can confirm would be great: > " just bought this monitor a few days ago and thought I would share > some tips for Mac users. If you have a macbook pro I highly recommend > that you also buy a display port 1.4 to usb c / lightening cable to > use with this monitor. The included hdmi cable (or any other I've > tried) will not get you the full 75hz refresh rate on 3440 x 1440. > Also the display port cable produces a cleaner overall image + text. > Through hdmi... it was really bad. I mean to the point where it was > nauseating to read text on my text editor."

So I've been using the *Mini DisplayPort to Dual-Link DVI Adapter* for years to connect to a DELL 3007WFP which only supports **dual-link DVI input**. Now I want to connect the new macbook pro (late 2016) with thunderbolt 3 to this monitor. There is no such thing as thunderbolt 3 to dual-link dvi. Called Apple and after one hour on the phone they told me to buy a thunderbolt 3 to thunderbolt 2 adapter in order to connect to the *Mini DisplayPort to Dual-Link DVI Adapter*. After a trip to the Apple Store and $29 less in my wallet that's for sure did not work! So now I'm wondering: man can go and go back from the moon, but it can't make this work? I don't want to have to buy another monitor to use with the new macbook pro :( Has anyone successfully got that to work? Which adapters? How did you connect them? Below the *Mini DisplayPort to Dual-Link DVI Adapter* I've been using for centuries:

I have a MacBook Pro (Retina, 15-inch, Mid 2015, OS X El Capitan, 10.11.5) with Intel Iris Pro 1536 MB connected to an external monitor: Samsung SE790C: - Resolution: 3440 x 1440 @ 60 Hz - Pixel Depth: 32-Bit Color (ARGB8888) - Mirror: Off - Online: Yes - Rotation: Supported - Connection Type: DisplayPort - Television: Yes Every time my MacBook wakes up from sleep, all my windows are back to the MacBook screen. I have a similar setup at home (same MacBook but with a Dell 26' monitor) and this does **not** happen. Anything I can do about that? If more info is needed, just let me know! Thanks in advance for any help on that!

When I plug my Mac into a DisplayPort monitor that has loudspeakers, the Mac's volume controls become disabled. Is Apple assuming that if I have external speakers I am so much better using their own volume control that I have to be forced to do it? That is annoying because the monitor's volume controls are buried in terrible menus accessed by terrible buttons on the back of the monitor. Also, if I am inside an app where I can select the audio device and I select the Mac's internal speakers, *the volume controls are STILL disabled*. Is there no way to control the volume of an app when an external speaker is connected even if the app is not using the external speaker????? Some additional info: It's a Macbook Pro 13" 2018 version. Using a Thunderbolt to Displayport cable, plugging in to a Dell monitor with speakers. In another location I use the same cable to plug in to Dell monitors with Displayport but without built in speakers in the monitors. At that location the volume controls remain active and they control the internal speaker in the laptop as they should.

I am using a MacBook Pro 2017 (two USB-C ports, running Ventura) and want to connect it to a Dell P2415Q monitor. For that reason, I have bought this USB-C to DP-cable . The monitor shows 4K @ 30Hz only, and I am unable to get 60Hz out of it. I am certain that the monitor supports 4K @ 60Hz over DP, because I have successfully used that with my last MacBook Pro. That the Computer supports it is out of question, and Amazon claims that the cable supports 4K @ 60Hz, too. Where (and how) can I find the problem?

I have a Mac Pro 5,1 running macOS Monterey via Open Core Legacy Patcher (OCLP) and I just purchased a flashed RX 6600 video card from MacVidCards.eu . According to the specs on the MacVidCards website, the card is capable of 8k @ 60Hz. The card I purchased appears to be a flashed XFX Speedster SWFT 210 AMD Radeon™ RX 6600 with the following ports: > ‍DisplayPort: 1.4 with DSC > HDMI™: 2.1 VRR and FRL The manufacturer website does not include maximum resolution in the specs, but the same card by Sapphire does: > HDMI™: 7680×4320 > DisplayPort1.4: 7680×4320 So I have no reason to believe this card should be incapable of achieving 6k @ 60Hz. My monitor is a Dell UltraSharp 32" 6K HDR Video Conferencing Monitor . It is capable of 6K 6144 x 3456 at 60 Hz. In addition to Thunderbolt 4, it has the following video inputs: > HDMI 2.1 > Mini DisplayPort 2.1 I have purchased 3 different video cables: - 8k mDP 1.4 cable: https://www.amazon.com/dp/B0CL6GH63X - 16k mDP 2.1 cable: https://www.amazon.com/dp/B0CHVSPNCZ - 8k HDMI 2.1 cable: https://www.amazon.com/dp/B09CHH8TRC Using either of the 2 mDP cables connected to my PC with an RX 2080ti, the monitor reports a resolution of 6k @ 60Hz, 24-bit: Using the HDMI cable on the PC with the 2080ti, I get 4k @ 60Hz, 24-bit: Now, using the same DP cables connected to the RX 6600 in the Mac, the monitor will only sync to 5k @ 60Hz, 24-bit: Finally, using the same HDMI cable connected to the RX 6600 in the Mac, the monitor will only sync to 5k @ 60Hz, 30-bit: While connected to HDMI, running the following command on Terminal results in the following output: system_profiler SPDisplaysDataType |grep Resolution > 2024-03-31 12:30:55.464 system_profiler[43589:961215] Device PreExisted [000000010000076f] AMD Radeon RX 6600 > Resolution: 5120 x 2880 (5K/UHD+ - Ultra High Definition Plus) Since posting this question, I also found something interesting. While using HDMI, I can increase the resolution (scale up??) to what "looks like" 3008 x 1692 (have been running 5k with what "looks like" 2560 x 1440). Running the system_profiler command again, here's what I found: > 2024-03-31 12:37:46.658 system_profiler[43745:966153] Device PreExisted [000000010000076f] AMD Radeon RX 6600 > Resolution: 6016 x 3384 The screen still looks clear, and here's what System Profiler shows: But, the monitor is still only connected/synced to the computer at 5k: I can increase the resolution all the way up to 7680 x 4320 (8k) and the image is clear, but the monitor is still connect/synced at 5k and the System Profiler shows: > 2024-03-31 12:46:57.626 system_profiler[43945:973094] Device PreExisted [000000010000076f] AMD Radeon RX 6600 > Resolution: 7680 x 4320 (4320p/8K UHD 2 - 8K Ultra High Definition) System Profiler shows: It's worth noting that my M2 MacBook Pro connected via Thunderbolt connects to the monitor at 6K @ 60Hz, 30-bit and the available resolutions in Sonoma are different that what I'm getting on the Mac Pro. For example, on the MacBook Pro, I can set the resolution all the way up to 6144 x 3456, or I can set it to half this, 3072 x 1728. Neither of these options are available on the Mac Pro in Monterey. It's hard to say for sure, but the Macbook Pro appears to be just a tad sharper. So am I truly achieving 8K (surpassing 6k even), or am I running at 5K and just scaling?

I have a 15" 2019 MacBook Pro and a LG 34BK95U monitor (business version of 34WK95U - same hardware, longer warranty). The correct resolution of the monitor is 5120x2160 and sometimes everything works at that resolution. But, sometimes when I connect my MacBook (via ThunberBolt 3) or when it wakes from sleep already connected, it sends a 3440x1440 image to the monitor, which looks fuzzy and gets a warning from the monitor about the incorrect resolution. When this happens, the MacBook doesn't even give me the option of using the correct resolution in system preferences - even if I Option-click on Scaled, the highest resolution available is 3840x2160. This makes me suspect it's using DisplayPort 1.2 instead of 1.4, because I believe that's the maximum resolution DP 1.2 supports. Sometimes disconnecting and reconnecting the cable fixes it, sometimes switching to a different TB3 port in the MacBook fixes it, sometimes rebooting the MacBook or the monitor fixes it, but nothing reliably fixes it, and sometimes I go through all of the above and still have the wrong resolution. (To reboot the monitor, I just unplug it from the wall, wait a few seconds, then plug it back in.) I mainly use the ThunderBolt 3 cable that came with the monitor, but I also tried a short passive TB3 cable - same results. It also forgets the arrangement of the display relative to my MacBook's screen when using the wrong resolution; it remembers when it uses the correct resolution. In 🍏 > About This Mac > System Report... > Graphics/Displays, it has the display connected to the Radeon Pro 550X with the following info: LG HDR 5K: Resolution: 3440 x 1440 (UWQHD - Ultra-Wide Quad HD) UI Looks like: 3440 x 1440 @ 60 Hz Framebuffer Depth: 30-Bit Color (ARGB2101010) Mirror: Off Online: Yes Rotation: Supported Automatically Adjust Brightness: No Connection Type: Thunderbolt/DisplayPort I'm currently on macOS Catalina 10.15.4, but this also happened on previous versions, including Mojave releases. It also sometimes turns on HDR mode when using the wrong resolution, which just has the effect of making everything a little darker. I think that started with the Catalina update. After reading https://apple.stackexchange.com/questions/344608/incorrect-external-monitor-resolution-detected-true-resolution-not-available I went into the Color Sync Utility and Verify found one issue, but Repair couldn't fix it: Searching for profiles... Checking 35 profiles... /System/Library/ColorSync/Profiles/ITU-2020.icc Header message digest (MD5) is not correct. The file is locked. Could not be fixed. Repair done. 0 out of 1 profiles fixed. I also noticed that under Profiles > Computer > Displays there are 4 different "LG HDR 5k" entries. Not sure if that's related or not. After reading https://apple.stackexchange.com/questions/39931/external-monitor-has-wrong-resolution I tried resetting the NVRAM / PRAM, but that didn't fix it either. I also have a Windows PC connected via DisplayPort and it always works at the correct resolution. ---- Update: It seems to be getting worse. I've only been able to get the correct resolution once since posting this. And it went away as soon as the computer went to sleep. I tried connecting a CalDigit USB-C Pro Dock (which is actually Thunderbolt 3, despite the name) and then connecting it's DisplayPort output to the monitor. The port on the dock is labeled 4k, but it can actually output the full 5120x2160 resolution - but only at 30hz. The low refresh rate is annoying but better than the fuzziness of 3440x1440@60hz, so I'm going with it for now. There were a couple of times where I had to disconnect and reconnect the DisplayPort cable to get any image out, but one re-connection fixed it each time, making it far more reliable than the direct TB3 connection. I've also ordered a generic USB-C to DisplayPort cable, so I'll update again after I've had a chance to try that. --- Update 2: USB Type-C to DisplayPort cable behaves about the same as the dock - correct resolution, but only 30hz refresh rate. --- Update 3: I got a hold of a Windows laptop with thunderbolt 3, and it worked perfectly on the first try, and again after I disconnected it and reconnected it. So I think that points to a problem with my MacBook. --- Update 4: I now have a 2021 16-inch MacBook Pro with an M1 Pro chip. I switched the display back to DP 1.4 just to see if it would work, but it has the same symptoms as the older Intel MacBook. So, I'm back to DP 1.2, which usually works. (Occasionally the monitor will freeze when I wake the computer up, and the last time I rebooted the monitor to unfreeze it, the laptop crashed and rebooted as soon as the monitor came back on...) --- Update 5: I tried installing LG's "OnScreen Control" app and under monitor settings, it had a software update "Run" button that appears to have updated the monitor's firmware and resolved some of the issues. I went from (3.11, 0, 2.4) to (4.12, 16, 4.17), and I was able to switch back to DisplayPort 1.4 and get the correct resolution on the first try. I'll try to remember to post another update in a few months. --- Update 6: No further issues since updating the monitor firmware; it's been working well for over a year now!