Can someone tell me what temps are acceptable for idle/load?
I bit the bullet and bought myself a beefy PC (for me at least. 3080 and I9-10900K) as a divorce present and I feel like it's running pretty hot. The CPU is OCed to 4.9GHZ.
It idles around 50 and under load for like WoW and REVillage, it hits mid-high 70s but for Control at max with max RT settings it pushes mid to high 80's. Should I be concerned about these temps or is it reasonable?
Are you talking about CPU or GPU temps? Either way, that's a bit too high during gaming. While doing CPU-intensive stuff, it could get that high, as the above graph suggests, but games aren't CPU intensive because the GPU does the heavy lifting. The CPU shouldn't be getting that hot during gaming.
If you're talking about the GPU, that can be expected to reach 80C, but I wouldn't want it going much higher. I'm not sure about the 3080, but the 3070 FE (which I have) starts to throttle at 83C. If Nvidia, itself, thinks that the card shouldn't go above 83C, then I'd say that anything higher is not good. Have you overclocked that any (including increasing the power limit)? If so, I would undo it and test again. You could always undervolt it to make it run cooler, but, like the CPU, if it's running that hot, there could be a problem.
Something also to try is to take the side or cover off of the case and test again. If it runs much cooler, then the problem could be with the airflow in the case. Whoever built it for you may've screwed up by using a poorly designed case or not connecting the case fans or something. If you take the sides off, run the CPU and GPU at stock (non-OCed) settings and you're still seeing the high temps, then whichever component is overheating may not have been assembled or installed properly (ex. a problem with the thermal paste/pads).