The most visible improvement of Asus' newly introduced 4K UltraHD ROG Swift PG27UQX 27 inch monitor compared to its predecessor 
Swift PG27UQ is the increased number of LED zones for local dimming from 384 to 576.
Asus achieves this by improving the LED technology used for the backlight: instead of normal LEDs, the much smaller mini-LEDs are now used (2,304 in total - four in each case make up a local dimming zone). This makes it possible to achieve higher image contrasts and fewer artifacts such as halos by using even more zones with different lighting. The Asus ROG Swift PG27UQX, together with a peak brightness of 1,000 nits, meets the UltraHD Premium and DisplayHDR 1,000 specifications, which only a few monitors have been able to meet so far.
Asus ROG Swift PG27UQX
It also offers a maximum frame rate of 144 Hz and G-Sync Ultimate - one reason for the need for active cooling via two (quiet, according to Asus) fans, despite the increased energy efficiency (7%) and thus lower waste heat through the use of mini LEDs.
In addition, the professional DCI-P3 color space is covered by 97% and the popular Adobe RGB color space by 99%. The factory calibration ensures that each delivered monitor has a delta E value of less than 3. Asus has not yet announced any further technical data (the Asus PG27UQ had only one HDMI 2.0 and one DisplayPort 1.4 as well as two USB 3.0 ports) or the price - the reference point for the latter might be the previous model, which came onto the market for around 2,500 Euros, but the G-Sync Ultimate is said to drive the price higher.
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