Reboxing the HP U28

We recently bought an HP U28 4K 28” monitor to replace our aging and partly broken iMac 5K (late 2014 model). Settling on the U28 was not easy, since the iMac is still a great monitor today (not to mention a great furniture piece) and we didn’t want to downgrade.

My first impressions of the U28 were very positive. It looked and felt better in person than the renders suggested. The stand (both the base and the “arm”) are fully metal, presumably from aluminium. The image quality, judged only by my eyes, looked great, with nearly no off-axis “glow” that plagues the Dell S2719DC in the other room. It even had a setting to allow letterboxing 4:3 inputs!

I’d have liked to back those claims with some hard numbers from a borrowed colorimeter, but I sadly had to put the U28 back in its box the same day. There was some noticeable backlight bleed in the lower corners, but the main issue was how “squished” the panel was. Drawing a circle on A4 paper and aligning it with the monitor showed that the monitor’s version was about 6 mm too short.

It turns out that this is actually stated in one of HP’s specs sheets. There, the “active area” is given 62.09 x 34.12 cm, which means the panel is missing about 8 mm in height to a proper 16:9 aspect ratio. The same document also states an aspect ratio of 16:9, which I would consider as misleading.

I had no idea non-square panels were being made (why would anyone choose to do that?), but this is now in my ever-increasing list of ways a product can be ruined.

If you’re curious, our unit had an Innolux M280DCA panel, MST9U01N scaler, firmware version 1.0.4.0 and hardware revision IIM251, as stated by the service menu.