I picked up a 7900 XTX a couple months ago and I have not ran into any noticeable issues. However, I did upgrade from a A770 which was quite problematic at that time. I will say AV1 encoding quality was noticeably better on the A770.
Ive been using Arc for 1 month now and the drivers are abysmally bad and updates are not nearly coming at a quick enough pace. Software is the only thing that will save the GPU division and it looks grim.
You are throwing an unrealistic synthetic load at it, and it’s still at or under the Tj-Max of 90c. There is no cause for concern, you don’t need to RMA because you didn’t get a “golden sample”.
Par for the course my computer crashed installing this driver. I did a forced reboot and then the overlay UI wouldn't close and I was forced to kill it in command prompt.