Imagine this: you have I chose the Case fans you like.You installed enough for your PC case and oriented them correctly, but your gaming PC seems to overheat and throttle under high loads. What’s more, your fans seem to be on edge, intensifying on the smallest tasks when they’re still idle at the desk.
This is a very common thing, and if it sounds like your PC, there is something you can do before blaming the fans, your CPU, your application of thermal paste, or all of the above. Setting custom fan curves in BIOS It takes a few minutes of your time and provides many benefits to your system. You paid for performance and keeping the default fans doesn’t give you optimal cooling for your PC.
Your system fans are not working (yet)
The default settings are not doing anyone any favors.
my main pc use the AMD Ryzen 9 7900X with a 360mm all-in-one and is idling at 57°C. That’s not ideal, and neither is the default fan curve, which is too low for most of your graph, rising when the CPU is supposed to be idle on the desktop. I’m not too worried about the idle temperature, but it hits Tjmax and accelerates under sustained loads.
If that sounds like your computer, know that there is something you can do for free before you start replacing your CPU fans or cooler. That’s playing with the fan curves in BIOS to get higher RPM when the CPU is idle, plus shaping the curve to suit the acoustics of your fans and the point at which your CPU comes out of idle temperatureso that your fans don’t go up and down all the time.
It’s worth replacing the fans that came with your case.
With very few exceptions, the fans that come with your case are there to keep you going. They will not allow you to obtain maximum performance; They may not have PWM to control speed and often do not have enough airflow to meet the needs of your components. And some manufacturers, like Lian Li, often skip shipping case fans because they know they won’t be used and, as a result, will sell more cases at a slightly lower price.
Let’s talk about concrete numbers
Cooler hardware means more headroom
Every preset in a modern UEFI BIOS is designed to get your PC to boot on the first try. To that end, those presets are designed for worst-case scenarios, to accommodate any potential combination of PC case, case fans, CPU fans, and CPU TDP. That means it’s optimized for compatibility and first run, not later use.
While some motherboards have automatic features that will test the fans you have installed and create a custom fan curve from that, they still fall short when it comes to adjusting the sound profile, and that’s why I prefer to manually set the curve and adjust it to get a non-irritating idle and charging sound signature.
Quiet profiles are rarely good without slowing down the CPU; Standard profiles often start their speed ramp at a point where the CPU is mostly idle, and turbo settings crank that up to 11. None of these are designed for your specific hardware combination, and manually adjusting the fan curve is the answer.
Default fan curves
Well, to fully stress the CPU and test the default curve, it’s time to try Cinebench 2026. This also stretches the GPU to its maximum, which will show if increasing the airflow in the case also improves GPU temperatures.
- Maximum GPU temperature: 61.4 C
- Maximum CPU Tctl/Tdie Temperature: 95.9C
Not good CPU temperatures, but the Ryzen 9 7900X has been known to idle on high, ramp up to the top of its power envelope, and then slow down repeatedly to stay below the maximum Tdie temperature. Cinebench scores are respectable, with 327 single thread and 5,317 multithread.
Modified fan curve
I went into the BIOS to set a custom fan curve for the CPU fans, and all the case fans would run at 50% PWM until the CPU reached 50°C. After that, it slowly increases the speed up to 70 C, then puts all the fans on full speed to give a little more thermal headroom when under 100% load.
- Maximum GPU temperature: 60.1 C
- CPU Tctl/Tdie Max: 95.9C
Cinebench 2026 didn’t change the maximum CPU temperature, but the GPU temperature dropped by more than a degree, so there was clearly better airflow in my PC case. However, scores improved with 5,652 multithreading (6% increase) and 352 single thread (7% increase).
This has a measurable impact, all for taking a few seconds to change a BIOS setting. Note that the maximum temperature did not change, but the performance did. This is expected from modern CPUs, which are designed to throttle and then throttle to stay in the safe temperature range, not throttle to keep temperatures low.
Changing your fan curves gives you the best from your hardware
The default fan curve in your BIOS It’s conservative, so it doesn’t cook your PC on first boot. It is not designed to get the best performance from your hardware or to produce a pleasing ringtone for your fans. With a few tweaks, you can get excellent cooling performance while optimizing fan noise to a level you can live with at your desk. While some motherboards have a fan adjustment algorithm that tests the ones you have installed, I’ve always found that a little manual adjustment works best, but YMMV.
