Recently, I was able to purchase the BL2420PT at a special price from NTT-Xstore, which I believe is the cheapest monitor capable of displaying WQHD (2560 x 1440).
2560px for a 23.8 inch monitor is just right, and even if you split the display in half and display it on the left and right, you still have 1280px for web browsing, so most websites can be displayed without being cut off, and I'm very satisfied with how efficient it is. Full HD (1920px) is just halfway for websites. Full screen leaves too much width, half the screen cuts it off, and if you enlarge the browser size to display the entire website, you end up with unused width, so I think this resolution is the best if you're mainly using the web. Of course, for other uses, Full HD or 4K may be best. If you have space on your desk or are at a distance, I think a size of 27 inches or more would be better.
This was my favorite display, but after about two weeks, the display port connection to my Mac suddenly said "no signal detected" and the display stopped working.
It was too early, and it was a problem, but when I reproduced the phenomenon, Windows connected with HDMI was displayed normally. Even if I reconnected the display port to Windows, it didn't work, and even if I connected it to another macbook pro I have, it didn't work, so I suspected that the cable was faulty, but while investigating the same symptoms, I found that it was a frequent occurrence not only with the BL2420PT but also with Benq displays, so it was not a faulty cable.
The only solution was to unplug the display from the power outlet and leave it for a few minutes.
At first I was skeptical, but when I tried it I was able to recover my data.
The key seems to be that no matter how many times you plug and unplug the cable or turn the power switch on and off, it doesn't work until the battery is completely discharged.
I also tried switching the DisplayPort version between 1.1 and 1.2 from the display settings menu, and changing the settings on the BenQ Service Page, but after some unstable operation, such as switching the version temporarily fixing the problem and not being able to put the MacBook into clamshell mode, it stopped accepting even that and said "no signal detected." In the end, it seems that bugs in the firmware or something inside the display had accumulated and prevented it from responding, and that this was a mysterious setting that was resolved by completely discharging the battery.
Until now, I have never intentionally turned off the display power because it has an extremely convenient function called the ECO sensor, but from now on I will get into the habit of turning it off from the power outlet on a regular basis.
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