Six months ago I got an exceptional deal on a new in box, direct from Dell, U2413 wide gamut monitor. I plugged it in to my Mac mini and liked it immediately. I already knew that to calibrate the monitor internal LUT Dell forces you to use the XRite i1Display Pro. I soon found out that I had to buy a minidisplayport to DVI adapter to hook up the monitor to the Thunderbolt port to even get a wide gamut output, so I hooked up the old monitor, a Dell 2320L, with the HDMI cable I had been using and now have a dual display setup, which I also like very much except for one annoying occasional problem. Every once in a while the Dock moves to the second monitor. Don't know why, and don't know why it also moves back at some point. The HDMI port on a Mac only puts out Rec 709 color with its limited dynamic range of 16 to 235 in each color channel, so you actually can't even calibrate sRGB.
Anyway, I set the monitor to Adobe RGB, 6500, and 2.2 for starters, and the improvement in Adobe RGB embedded images was noticeable. The factory default Adobe RGB looked good and the spec sheet for the factory cal read really good numbers, so I wasn't sure I'd bother with getting an XRite. I did find a decent price and bought it. Googling for how to, I collected a bunch of web articles and a forum called Photography Life. This forum has a thread titled How To Properly Calibrate A Dell U2413. The beginning of the thread has a detailed procedure with pictures and links, followed by many comments from readers. There is at least one error, it says to set the monitor to "Native", but the U2413 doesn't have Native, so you have to guess that 6500 is close enough for government work. If you expend a lot of effort you can find the Dell UltraSharp Color Calibration Solution Software for Mac on the Dell Support page. This is version 1.5.3. I'll return to that in a bit.
The thread comments contain quite a bit of misinformation, confusion, and Windows advocacy, including a digression about Windows being the only way to go because it has 10 bit per channel color and Mac is not capable of that. Yeah, Win 7 and above can be set for 10 bit, with the right video card, but you might have to dedicate that machine to Photoshop, because it breaks most other apps. 8 bits does mean that you are only setting 256 points of a 16,382 point LUT, but even if you have a 10 bit pipeline, the U2413 is actually 8bit+FRC, so you are feeding an interpolation to an interpolation for whatever that is worth. It is doubtful that you will notice 10 bit anyway. Humans can only distinguish at most about six million colors if you include luminosity. 10 bit eliminates any real possibility of banding in wide color spaces at best.
To return to the Dell calibrate software. its folder contains a read me which says " Some Mac video cards may cause he computer to crash and fail to reboot to the desktop.Connect a second monitor and reboot, then reconnect the primary monitor."
Great. All you need is an ambiguous FUD statement before using a new device with a new monitor.
I contacted Bruce Wright at XRite on the recommendation of a thread commenter and told him I had tried Dell support in the past and it was a nightmare. He asked me to try them again and if they didn't help me to get a case number so that Xrite could deal with it at company level. After a half hour of penetrating the Dell support structure, I got another Indian in the Concierge area who appears not to know that Dell makes monitors, would not transfer me to someone who does, and would not give me a case number. I reported this to Bruce , who assured me they would take it from there.
He said this today, so it will probably be a week before I can find out anything.
What kind of an idiot would write a non specific warning that implies you have a second monitor to recover from a crash.