I recently upgrade my ancient Dell P2715Q 27in 4k IPS monitor from 2014 with a newish “rapid IPS” that uses quantum dots. Woo hoo! All aboard the hype-train we go. Techno jargon aside, motion blur with 120Hz refresh rate and “fast” response time is much better than the old Dell. However, “IPS glow” of the MSI is significantly worse and the biggest offender is color temperature (white point in kelvin) stability. (Possibly the worst “feature” of the MSI is the absolutely horrible fake HDR mode.) Using an X-Rite i1 Studio spectrophotometer to calibrate the display and observe the color temperature change during warm-up shows that the monitor will start (when “cold”) about 500 to 800 kelvin lower than the calibrated value (after 2hr warm-up). Then there is just a general instability in the white-point of about ±200 kelvin when the monitor goes in and out of standby (warm-cold-warm cycles). E.g., calibrating to 6500k will result in 6700k next 2hr warmup after standby… My old Dell with it’s “classic” white LED back lighting was very stable when going in and out of standby and saw minimal warmup time to reach stable color temperature. This MSI takes 2 hours to become stable and at least 40 minuets to settle within 200k of its final value. These quantum dots are a pain in the ass, but they do show measurable and quantifiable improvements in color gamut and generally a new paradigm in back light technology that allows for brighter displays and higher efficiency for the backlight. To see what I’m talking about (WRT color temperature), here are some screenshots of DisplayCal using my i1 Studio to monitor the display. Ignore the 8000k white point value–I was just playing around with different white-points and 8000k was the most stable over repeated on-standby-on cycles. (Yes, I like to waste time fiddling with things.) COLD (OFF or STANDBY >= 10min to ON) after 40min on time after 1hr on time after 1hr 30min on time Quantum dots spectra captured by my i1 Studio with 3.5nm resolution. The jaggies / clipping near the peaks is due to limited spectral resolution of this spectrophotometer. The hump in the blue plot is due to green bleed-through (some blue light is still emitted despite blue channel being off). Old reliable. My Dell P2715Q barely covered the sRGB range and had bad motion blur, but had great color temperature stability and very low IPS glow. (High resolution plot made with StellarNet BLACK-Comet spectrophotometer with 1.5nm resolution.) Compressed (logarithmic) vertical axis shows cross-talk between color channels. Notice on the Red plot, that the blue channel has some bleed-through. Then there is general overlap of each color’s emission spectrum that causes cross-talk. This second effect is where the quantum dots help, as each color channel has minimal spectral overlap–as shown earlier. Dell blue light emission spectrum (apparently bad for the eyes). AMMOLED (Samsung phone) blue light emission spectrum (less bad for the eyes). Older monitors with “white LED” backlighting like my Dell have a peak amplitude near 446.2nm, which is apparently bad for the eyes. Over 10 years of using it hasn’t made me go blind… yet, lol. Here’s a really cheap ($80) MSI 28G1UV 27in 4k monitor I bought that also has bad color stability due to the red phosphor having large amplitude spectral spikes and general instability in the red emission amplitude due to these spikes varying significantly with temperature. I specifically bought my new MSI for the quantum dots thinking that they would fix this issue, which they did not. Peaky spectral lines of phosphors and quantum dots both have bad temperature stability. Who knew? Not me apparently. MSI 28G1UV spectral plot. Look at the really bad green-blue spectral overlap. Also the smoking gun: massive spectral spikes for the red emission spectrum. Here’s the compressed amplitude plot. Hey! Why no high resolution plots of the MSI MPG 274URF QD? Because CachyOS / Arch broke virtual machine manager (and DisplayCall too!) by updating to python 3.14. So no WinXP VM to run my high resolution spectrophotometer. This is one of the reasons I like Fedora–or any point-release distro really–they make sure each package works before updating core dependencies like python. Arch makes getting the latest-and-greatest packages simple, but it also means latest-hath-borked the things you depend on too.