CPU usage consistently elevated during standby.
CPU usage consistently elevated during standby.
Stock 5800x suffers from limited airflow. Only 240 units available, but largely due to a subpar design for AIO systems. The radiator is mounted horizontally; the pump sits high, which isn't ideal as it should not be the top point in the loop. These AIO models generally disappoint overall. Still, idle temperatures don't tell the whole story—what matters is how performance holds under full load (not gaming). For instance, Cinebench all-core clockspeed reflects this under real conditions. Only then can you assess if your cooling setup is sufficient. Keep in mind, the 5800x will generate more heat since all eight cores are active together in one CCX, creating significant thermal pressure in a compact area. The 5900x, for comparison, runs at 6 and 6 under similar conditions. In an optimized airflow case, some tuning with PBO Curve Optimizer and a 360 AIO can keep idle temps around 35°C while maintaining 4.7GHz all-core speed.
For beginners, start with a case like MSI MEG or ASUS ROG Maximus. Pair it with an AIO such as the Noctua NH-D15 or Corsair H3. Watch this guide: https://www.youtube.com/watch?v=QkLqZ9lQ5gA
Average temperatures during maximum demand are around what you see with your 3900x model.
Your temperatures are projected for the 5800X. Mine stays in the mid-to-high 30s to low 40s when idle, and your stress temps are within normal range. Below is a brief screenshot of its performance and some readings during gameplay.
If it’s an MSI cooler, I’ve noticed videos showing issues mainly with MSI coolers, often due to faulty coolant. You can check a spare cooler to see if the problem is real. Also, wondering if this setup is fully MSI—since the case and GPU are also from MSI—but the temperatures differ a lot, ranging from 85-110 during load to 50-60 when idle.
The issue remains unresolved, and what's considered "known bad" on forums is still significantly better than the average OEM output. The heat concern isn't just another weak claim from gamers.