I can't say. Do you think it's defective? Can you measure the temps? And what is your ambient temp?

The AUO M270Q002 V0 TN display panel chemistry is rated to operate up to 100C, the electronics are probably generic commercial-grade stuff rated to operate up to 85C (although the factory-overclocked G-Sync module uses a big fat heatsink and requires extra venting, so it might be better-grade stuff rated for higher temps). The hottest points measured (with an infrared thermometer at 19C ambient) on my PG278Q when running at full spec were 35C near the top area of the display panel and 43C immediately under the enlarged back area (where the electronics reside). The metal chassis/frame parts (under the bezels, etc) were all cooler than that big fat G-Sync heatsink. The LED temps were inconsequential.

The PG278Q complies with Energy Star 6.0 standards, meaning entire unit must be rated for <0.5W standby/off and <90W full power consumption. My PG278Q measured (with a Kill-A-Watt meter and a decent DMM) a draw of <1W on standby and hovered around 50W when running at maximum spec.

Your settings are being operated within the rated maximum spec for the monitor. You can compare temp/power measurements between your unit and mine, if that helps.

I think a TIM is a terminal interface material. The monitor has a heatsink inside of it. That will normally get hot. How hot? I don't know. I don't know where in the monitor it is, but it may be in the spot that your monitor is getting hot at.

RUMOR - I read somewhere, but I can't recall where, "that the SWIFT will go in overclock mode when running at 144HZ." This may or may not be true. But you might want to experiment with running it at 120HZ or lower to see if the temperature runs lower.

I'd contact ASUS's tech support by email to see if you can get a definitive answer on what are the acceptable temperatures for it to run at. It's possible that it running normally. Then again, maybe it's not.

Another possibility is to check all the vents on the monitor to make sure there isn't any lint in them obstructing the air flow. If it's new, this is unlikely to be the case. But a quick check wouldn't hurt. With my computer, my apartment is very dusty. And within a short period of time, my computer and it's vents will get dusty and linty. When that builds up sufficeiently, then the computers fans will work much louder as the rig gets hotter. Not dangerously hot. But it gets very noisey. Cleaning out all the built up lint, makes it much quieter.

Ahh - found an old thread that sounds like it has the same issue you are having.

https://rog.asus.com/forum/showthread.php?53622-Asus-PG278Q-heat-issue

Then it looks like it's going to be okay. Especially if ASUS supports said that the temp was acceptable. Then I wouldn't worry too much about it.

This reminds me a little bit of how my desktop will run hotter, or cooler depending on what it's doing. I have my desktop under, and next to my desk. And it's in the corner of my living room area. If I play a long session of Far Cry 4, I'll sometimes hear the fans become louder. And my area under my desk will get noticably warmer. I have to run the AC and another ceiling fan to help keep my computer area cool and comfortable. I've never really noticed my SWIFT getting noticalblly warmer. Nor have I ever really checked. For I mostly notice when my desktop pushes out hotter air. I'll try to check it when I'm gaming to see if it get's hot (50°C) like yours does.

The inside of my desktop, and it's componenets will get very hot. It's designed to do that. And normally lasts for several years.