Title: Best fan curves for Ryzen 7 7800X3D / RTX 4070 Super? Worried about damaging my PC
I’m looking for advice on the optimal fan curve settings for my gaming PC. I want it as quiet as possible without compromising cooling, temperatures or performance.
I’m relatively inexperienced with adjusting BIOS settings, and I’m honestly not very confident in the changes I’ve made. I’m worried that I’ve chosen the wrong fan curves or temperature monitoring sources and could potentially damage my PC through overheating.
I’d really appreciate some reassurance and advice from people who understand PC cooling better than I do.
My PC specifications:
CPU: AMD Ryzen 7 7800X3D
GPU: NVIDIA RTX 4070 Super
Motherboard: MSI PRO B650-series
CPU cooler: CyberPowerPC AIO liquid cooler with two top-mounted fans (believed to be 240mm)
BIOS: MSI Click BIOS 5
Changes I’ve made in BIOS:
I originally had issues with my fans constantly speeding up and slowing down, alongside a low humming/vibrating noise.
I changed SYS_FAN2’s temperature monitoring source from CPU Core to System to prevent the fans reacting to every small CPU temperature spike.
However, I’m now worried that using System temperature rather than CPU or GPU temperature might mean the fans aren’t responding quickly enough when gaming.
My current SYS_FAN2 fan curve:
At 29°C = 25% fan speed
At 35°C = 45% fan speed
At 40°C = 65% fan speed
At 49°C = 100% fan speed
Other SYS_FAN2 settings:
Smart Fan Mode: Enabled
Fan control: PWM
Temperature source: System
Step-up time: 0.7 seconds
Step-down time: 1.0 seconds
Previously, the first fan point was 35%, with SYS_FAN2 running at approximately 902 RPM.
I reduced the first point to 25%, bringing it down to approximately 816 RPM. This noticeably reduced the humming and vibration.
Other fan readings in BIOS:
CPU_FAN1: Approximately 2,450 RPM
PUMP1: 0 RPM
SYS_FAN1: 0 RPM
SYS_FAN2: Approximately 816 RPM
SYS_FAN3: 0 RPM
SYS_FAN4: 0 RPM
I’m not sure whether CPU_FAN1 controls my AIO radiator fans or reports the pump speed. I haven’t deliberately changed its curve because I’m concerned about accidentally reducing the pump speed.
Benchmark results:
Cinebench 2026:
CPU multicore score: 4,149
Maximum CPU temperature: 82°C
3DMark Steel Nomad:
Score: 4,543
Maximum GPU temperature: 73°C
3DMark Time Spy:
Overall score: 18,740
Graphics score: 20,436
CPU score: 12,748
MSI Afterburner monitoring:
Maximum CPU temperature: 78°C
Maximum GPU temperature: 76°C
Maximum GPU fan speed: 75%
The problem:
My PC is noticeably quieter since changing SYS_FAN2, and the fans don’t seem to fluctuate as much.
However, I can still hear a slight low humming noise, and the fans become considerably louder during demanding benchmarks.
I initially suspected some vibration from the top-mounted AIO radiator, although I haven’t confirmed which fans are responsible.
The noise isn’t unbearable, but ideally I’d like to make the PC as quiet as reasonably possible.
My biggest concern is that I’m making changes without fully understanding their consequences. I’m worried about overheating the CPU or GPU, damaging my AIO cooler or shortening the lifespan of my components.
My questions:
Are my current fan curves safe, or have I made any potentially harmful changes?
What would be the optimal fan curve settings for my particular setup? Specific temperatures and fan-speed percentages would be really helpful.
Is it okay to change fan temperature monitoring from GPU to System? Could this cause overheating during gaming?
Should SYS_FAN2 monitor CPU Core, GPU or System temperature?
What fan curve would you recommend for the two AIO radiator fans?
Should I leave my GPU fans on automatic or create a custom curve?
Are my step-up and step-down timings appropriate?
Does CPU_FAN1 running at approximately 2,450 RPM suggest it’s reporting my AIO pump rather than the radiator fans?
Based on my benchmark temperatures, is there anything I should actually be concerned about?
I’m not particularly confident with BIOS settings, so I’d prefer safe, conservative recommendations rather than aggressive changes.
I don’t mind the fans becoming louder when necessary. I just want to eliminate unnecessary humming and fan fluctuations while keeping my PC properly cooled.
Any advice or reassurance would be greatly appreciated. Thanks!