Ideal temperature ranges for VRMs during locked processor operation
Ideal temperature ranges for VRMs during locked processor operation
Hello everyone, I have a query regarding the ideal temperature range for the VRMs in my setup. I’m using a Gigabyte Z370HD3P with an i7-8700 non-K processor, and the case has fans set to run continuously. The fans are positioned in their default setting, but I’m unsure how to adjust the rear fan since my motherboard automatically assigns it to the VRM sensor, which makes things noisy at high temperatures. The fans aren’t as quiet as they claim. I’ve observed that VRM temperatures rise significantly—reaching around 85°C during intensive tasks like Prime95. I’m not sure about the optimal safe range, as opinions vary widely: some suggest keeping them below 80°C, others believe 100°C is acceptable, while a few say 125°C or even 150°C is within limits. The temperature span from 80°C to 150°C seems quite broad. Should I aim for specific idle or load temperatures? Does it depend on the motherboard model? Or is it safe to proceed without strict limits? Also, since I’m using a locked processor, does that change the situation? Thanks in advance for your insights.
VRM temperatures below 125°C are fine, and several VRMs handle levels under 150°C. It's not a semiconductor issue, so the 100°C limit for your CPU doesn't apply.
The silicon in most computer mosfets can withstand temperatures up to 150°C, but this usually translates to around 125°C inside the package. The components near the VRM are less reliable, typically rated for about 5000 hours at 105°C. High-end boards may handle more cycles, while budget models can last only 2500 hours at 105°C or even 5000 hours at 80°C. Temperature has a strong effect on capacitor life, decreasing rapidly as it rises. If your mosfets operate at 100°C, the recommended capacitor range is between 60-90°C based on location, airflow, and heatsink design. This is why keeping the temperature limit high is important. Some inexpensive boards have faulty thermistors, which can misread the mosfet temperature. Therefore, readings should be taken cautiously. The heatsink appears adequate, so it shouldn't be a major concern unless you're using a specific driver IC.