Yeah, that has been confirmed at least a few times here. Works out of the box at 60Hz with nMP and recent rMBP with the supplied MDP to DP cable. Only real issues is a lack of boot screens due to lack of EFI for 4K 60Hz SST.
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Dell P2715Q and P2415Q 4K IPS Displays
- Thread starter VirtualRain
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Yeah, that has been confirmed at least a few times here. Works out of the box at 60Hz with nMP and recent rMBP with the supplied MDP to DP cable. Only real issues is a lack of boot screens due to lack of EFI for 4K 60Hz SST.
So operating a rMBP in clamshell mode won't work unless its always kept in sleep mode, and when rebooted needs to have the main display on to login?
The display lights up at the login screen... The only issue is if you want to choose another volume at boot or access the recovery partition but for those times where you need that you can hook it up via HDMI and it will work at 30Hz to do those kinds of tasks.
Ah OK, thanks for the info! Will probably place my order for the 24" model in the coming week(s). After getting the rMBP I can't go back to using a standard display anymore.
OK, more testing. Maybe one of you gurus can figure it out. On my oMP with the GTX 670, here again, under 10.10.1, the monitor defaults to 1920x1080. In Win 7, as I noted earlier, it defaults to 3840x2160 at 60. No user input required. On the oMP with the Nvidia card, I still have to select 3840x2160 with the option key. Strangely, I get higher scaled options, and yes these are obviously pixel doubled (but labelled low resolution), but 3840x2160 is there as are lower resolutions of course, with some of these having the :low resolution" option.
3840x2160 appears only once, with no "low rez" in parentheses, but still only as a scaled rez. However, a screenshot is 3840x2160. Here's where it gets weird. Whether the monitor is obviously running at 1920x1080 and system info does show that rez, the screenshot is still 3840x2160! If 3840x2160 is selected as a scaled option, then the screen runs at that rez and sys info proves it at 3840x2160...AND...the screenshot is still 3840x2160. So, whether the monitor is obviously running at 1920x1080 via best for display, or 3840x2160 via scaled (the only option), the screenshot is still 3840x2160 for both. What the heck is going on????
3840x2160 appears only once, with no "low rez" in parentheses, but still only as a scaled rez. However, a screenshot is 3840x2160. Here's where it gets weird. Whether the monitor is obviously running at 1920x1080 and system info does show that rez, the screenshot is still 3840x2160! If 3840x2160 is selected as a scaled option, then the screen runs at that rez and sys info proves it at 3840x2160...AND...the screenshot is still 3840x2160. So, whether the monitor is obviously running at 1920x1080 via best for display, or 3840x2160 via scaled (the only option), the screenshot is still 3840x2160 for both. What the heck is going on????
Reading up until this I've been knowing you'd get to this point.
1920x1080 Best For Display is RETINA. It's pixel doubling the UI. It's effective space is 1920x1080, but it's actually 3840x2160.
Any res higher than that until native should be still rendering a Retina image, but then scaling to fit the display and create the usable space of the res you have chosen.
Download SetResX and set the resolution to 1920x1080 using that, it should output genuine 1080p and look horrible and fuzzy. Can also use it to select native and see what it's doing that way.
Basically Apple don't think you should be using the display at literal native resolution, wanting you to use a retina UI instead. Content such as FCPX, Photoshop etc still renders the working media as 1x, so you can still view 4k content on it, just all the UI is bigger but ultra sharp.
Going back to my previous point, you cannot trust any resolution except what you see in the Dell OSD Menu. Because of the way that OSX does HiDPI on 4K displays, you can't tell by looking at either the OSX System Information or the Display Preferences what the real resolution being sent is. Out of curiosity, based on your posts, I tried a few different resolutions, both "scaled" and "low resolution". At least on an nMP, it appears that it will always send either 3840x2160 or 2560x1440 to the monitor, depending on what it thinks is necessary to render the resolution you choose, even when you select "low resolution" which is supposed to always use a monitor's preset display modes, but which is not happening in this case. You can see this in the OSD Menu, where for most resolutions it says "Resolution: 3840x2160, 60Hz" except for a few resolutions where it says "Resolution: 2560x1440, 60Hz". Under Bootcamp, you can get it to send any of the supported resolutions and when you go to the OSD Menu, you see the expected resolution. For what you want to do, you're basically looking to disable HiDPI and have OSX behave more like Windows.
OK. It's starting to make more sense. However, ignoring how much I hate Apple or anyone else choosing something I want control over for me, it is my understanding that applications have to be optimized for Retina in order for the UI to be scaled nicely but for higher rez image content appear natively (e.g., UHD video or still at that rez). Correct?
Oh, and don't get me started about how crazy using both this UHD monitor and a TB display together is. From resolution, to scaling, to arrangement, OS X is doing things I am NOT telling it to do and do not want. Turn a monitor off, no problem. Turn it back on, things get weird. Lots of rearranging and resetting. Win 8 was a disaster initially, and somewhat still is, but it "just works" with UHD, as does Win 7, even on the old MP with the 5.1 firmware hack and a PC Nvidia GPU. Snow Leopard was great, but since then, it's been all downhill for OS X. Sure there are some cool new features, but power usability isn't one of them, and things don't simply "just work" anymore as they should, or at least as over 30 years of using computers of many varieties has led me to expect from an OS and/or UI. DOS was more intuitive than Yosemite. Rant over, and thanks for the help.
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Well, 3rd tier Apple told me to only trust the system profile data which is a poll of the data stream, but I see what you are saying. Nevertheless, if a monitor is 3840x2160, then I expect it to run that way assuming the GPU, cable, et al are capable of it. Whether it is my nMP or oMP, the issues I have apparently are with OS X and Apple telling me what is best, which is not always best for my professional purposes. Actually, they don't tell me anything. It all happens behind the scenes and regaining control is NOT obvious. Two hours on the phone with Apple today did not get me answers as good as I've gotten in the last ten minutes here. Thanks guys.
@xav8tor I think what you may want to do is try out SwitchResX. It should let you disable the HiDPI mode and use the monitor at whatever native resolution you want to work at. It's shareware but pretty cheap. There are some other alternatives (SetResX, QuickRes, scrutil, etc.), but I haven't had experience with those, and the author of SwitchResX has been very responsive on support issues to people on these forums who have needed help with 4K displays.
That's how retina displays work. Best for Retina uses four times the pixels to render a 1920x1080 desktop very sharp at 3840x2160 (2x scaling). Any scaled resolution (not counting native) like 2560x1440 is first rendered at double size (e.g 5120x2880) to take advantage of the high res retina artwork and then down sampled to the display resolution. 2560x1440 (1.5x scaling) will also look incredibly sharp as a result.
Any desktop screenshot of a scaled resolution will be double-size as this is the effective desktop resolution OS X is working with before its down sampled for display.
When you select 3840x2160 (native) no scaling is taking place so your effective and displayed desktop is a 1:1 or 3840x2160.
wait so if i want the retina all i have to do is select best to scale? in this case 1080p? and i'll get the retina?
I now have the same display setup as you!
I'm surprised by how the P2715Q doesn't look that much bigger than the 2407WFP when you put them side by side, due to the latter being 16:10. They almost have the same height, which is great for a dual-monitor setup.
Yes. Unless I misunderstand your question. "Best for Retina" on a 4K display will give you a desktop similar to 1920x1080 that's ultra sharp but your content (images, video, etc) in Retina-aware apps will render it 1:1 so you can edit a full 1080p video in FCPX and see every pixel while having your UI, controls, text etc at retina sharpness.
There's a very simple way to tell the real resolution which OSX is using:
Press Cmd+Shift+3 to take a full desktop screenshot.
Open the image on your desktop in Preview.
Select Tools / Image Size.
OSX likes to do up/downscaling in the compositor so the monitor will report that you're always running at its native resolution even if you're not. "Best for display" should be the native res unless something went wrong with detection.
Don't believe System Settings when it tells you it's 1920x1080. It says "looks like" for a reason.
Press Cmd+Shift+3 to take a full desktop screenshot.
Open the image on your desktop in Preview.
Select Tools / Image Size.
OSX likes to do up/downscaling in the compositor so the monitor will report that you're always running at its native resolution even if you're not. "Best for display" should be the native res unless something went wrong with detection.
Don't believe System Settings when it tells you it's 1920x1080. It says "looks like" for a reason.
Thanks. I'll try it.
From the other recent posts, I see there is still some confusion and misinformation out there, and the way OS X handles the so called "Retina" displays is part of it. FYI "get info" on a screenshot gives you the image size without firing up Preview, tools, yada, yada. Dell menu states native rez no matter what I set display prefs to. Remember, with the option key, you get actual resolutions, not "looks like," but the monitor still may be running native. Sys info will report what you selected. Also, it's "best for display" not "best for retina," (unless that's specific to the rMBP), both being Apple coined terms, which is part of the problem for people used to being in full control of their computers like in the "old days."
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Bad news. Had first wake from sleep failure with the 24" this morning after a good night's sleep. OS X still "saw" the Dell, but there was no way to wake up the monitor, which had a black screen...nothing. Power button did not work - at all. It was lit and stayed lit, no matter how many times I pressed it. Menu buttons didn't work either. Had to unplug the monitor to get it back. Didn't get to try "detect displays" because guess what? Apple hid that to (use option key...again). It would be a pain to have to do, but better than doing gymnastics to unplug my setup. Then again, since display prefs was showing dual displays, detect display button punching may have had no effect either. Will try it next time the monitor doesn't wake up, and at this point, I'm quite certain there will be a next time!
Now this thing makes me feel like I do under the knife, wondering if I'll go to sleep and not wake up, and if so, in what state?
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On the rMBP "Best for display" is a radio button, and "Best (Retina)" is one of the scaled options both of which are 2x scaling. Screen shot below. So my apologies for confusing terms.
I think Apple could clear this mess up by having four options:
- Native resolution (3840x2160)
- Best for Retina (looks like 1920x1080 at 3840x2160)
- HiDPI Scaled (select one for display at 3840x2160)
- LoDPI Scaled (select one)
That sucks. Hopefully Apple can sort this out with an upcoming OS X release.
Attachments
Yes, you're right, it's "Best for display", not "Best for Retina". I've attached a screenshot (which I had to convert to JPEG for the MacRumor's max file upload size) showing how the System Information Display tab, the System Report, the Display Preferences, and Get Info from full screenshot all show different information. The thing that creates the most confusion, IMHO, is that the System Report, which should have the most accurate information, instead reads "Resolution: 1920 x 1080 @ 60Hz (1080p)". The Display Preferences at least says "Looks like 1920 x 1080" although that's still somewhat confusing. However, you can zoom into the screenshot and see the screen is being rendered and sent to the monitor at 3840x2160.
Attachments
FYI looks like the 24" model just went on sale today in the US for $70 off, for $529: http://accessories.us.dell.com/sna/productdetail.aspx?c=us&l=en&s=bsd&cs=04&sku=860-BBFF
Given all the problems both Mac and PC users are having, the lack of support, and snobbishly so, when used with Apple machines, the fact that 24 inch models are warrantied differently (just found that out), etc. an so, you can bet I'll be asking some first tier customer support agent in a far flung land for a 70 buck credit tomorrow. Failing that, I'll try to give the credit card bank a copy of Dell's policy on price drops and get a credit on the back end and let them fight it out. Only problem there is the bank's call center is in the same vicinity as Dell support is, probably next door. Yes, I am getting cranky about this whole thing.
Thanks. Fortunately, in the first 30 days, there are a few ways to do it.
From what I gleaned on the Dell forums at first glance today, they have a really convoluted price match/drop policy that confuses even their own people. Ditto for the warranties, but less so. Apparently, monitors 24 inches and below are treated differently. With the larger ones the repair v. replacement policy is different, as is whether you get a refurb or new unit is as well. 24 and below also has no service tag, but rather, some sort of ID tied to the sale, which also can affect when the clock ticks if you by from someone other than Dell. None of this is readily apparent from the point of sale until delivery. Only when you have an issue and look into it, or contact them, do you become aware of things.
Half of it is probably illegal here in the US under various federal consumer protection laws, but unless you really know your stuff in that regard, they can stick it to you and get away with whatever they want 99.99% of the time, whether the warranty and/or replacement policy, or any other sales related issue, is actually legal or not. Happens hundreds of thousands of times per day. Sure Apple has occasional problems, but they are FAR more fair and transparent than most other tech related vendors out there, or any other type for that matter.
I've only got my P2715Q up and running in the past few hours, but so far, I couldn't be happier.
I've got a 2009 Mac Pro with a standard (PC) GTX 760 graphics card, running 10.10.1. I find 2560 x 1440 scaling to be best, but 3008 x 1692 might also be usable if I fiddle with text size. Owners of the 24" model may have better luck with the "best for display" resolution, but it doesn't work well at 27". I have a 60hz refresh rate; there is no option to select anything different. All rotation options are available. I am using a DisplayPort-to-DisplayPort cable. Wake from sleep seems to be working fine. (Although, I have to say that power button - which fades on and off while the monitor is asleep - is incredibly annoying.)
No boot screens, but of course I wouldn't have them anyways with my graphics card. I'd like to see what happens if I reinstall my GT 120 in a free slot and connect to the monitor using one of the other inputs.
I haven't calibrated the monitor yet, but brightness and color seem uniform. Great ergonomics, and not-bad design, either (at least compared to the cheap, smaller Dell monitors that I'm used to from my office). The antiglare coating doesn't bother me at all. I'm very happy with my purchase.
I've got a 2009 Mac Pro with a standard (PC) GTX 760 graphics card, running 10.10.1. I find 2560 x 1440 scaling to be best, but 3008 x 1692 might also be usable if I fiddle with text size. Owners of the 24" model may have better luck with the "best for display" resolution, but it doesn't work well at 27". I have a 60hz refresh rate; there is no option to select anything different. All rotation options are available. I am using a DisplayPort-to-DisplayPort cable. Wake from sleep seems to be working fine. (Although, I have to say that power button - which fades on and off while the monitor is asleep - is incredibly annoying.)
No boot screens, but of course I wouldn't have them anyways with my graphics card. I'd like to see what happens if I reinstall my GT 120 in a free slot and connect to the monitor using one of the other inputs.
I haven't calibrated the monitor yet, but brightness and color seem uniform. Great ergonomics, and not-bad design, either (at least compared to the cheap, smaller Dell monitors that I'm used to from my office). The antiglare coating doesn't bother me at all. I'm very happy with my purchase.
Thanks for sharing. Glad to hear you're happy. With some Dell displays there's an option buried in the on screen menus to disable the power LED. I'm not sure if that's the case with these models.
MacBook 15" Late 2013
Hello,
I have a Macbook 15" late 2013 Nvidia GT 750 2GB GDDR with two Thunderbolt ports. Is it possible to run a on Dell P2715Q UHD 4k in the first port at 60Hz and on the second thunderbolt port a Dell 21" screen at 1920x1080? Now I am using an Apple 27" Thunderbolt as the main desktop screen and secondary is the Dell 21" without any problems.
So the question: is the Macbook able to run both displays at the same time? I am planning to replace the Apple 27" screen with a Dell 4K, but I am a little concerned that it will function well.
Thank you for your respons.
http://support.apple.com/en-us/HT202856
Hello,
I have a Macbook 15" late 2013 Nvidia GT 750 2GB GDDR with two Thunderbolt ports. Is it possible to run a on Dell P2715Q UHD 4k in the first port at 60Hz and on the second thunderbolt port a Dell 21" screen at 1920x1080? Now I am using an Apple 27" Thunderbolt as the main desktop screen and secondary is the Dell 21" without any problems.
So the question: is the Macbook able to run both displays at the same time? I am planning to replace the Apple 27" screen with a Dell 4K, but I am a little concerned that it will function well.
Thank you for your respons.
http://support.apple.com/en-us/HT202856
You might need to use an HDMI to DVI cable for the second monitor. I'm not sure if there's enought bandwidth left on the Thunderbolt controller of the MBP to driver the second monitor.