Motherboard VRM thermal testing – budget vs. high-end boards, does it really matter?

If you’re a PC enthusiast, chances are you’ve bought or at least looked into picking a motherboard, and it can be daunting. The list of specifications is long and includes (but is not limited to) CPU support/compatibility, port count and type (think USB, networking, etc.), storage options, audio solutions, slot count and speed, aesthetics, and last but not least, power delivery, which is critical to ensuring you get everything out of your processor. Should you buy a board with more phases or more powerful MOSFETs? What’s good enough? Using data from our motherboard reviews, we’ll examine details such as temperature and performance to assess the magnitude of the differences and whether power delivery should be a key factor when choosing a motherboard. What are VRMs? Some may be reading this and asking, "What are VRMs?" VRM stands for Voltage Regulation Modules. Their primary function is to take the 12V power from your power supply and reduce it to a lower, stable voltage (around 1-1.5V) that your CPU and other components need to function. Or, in electrical terms, they are advanced DC-to-DC step-down converters tasked with smoothing out electrical noise and voltage spikes, which could crash your CPU. If they seem important based on that description, congratulations, you are paying attention. VRMs are not a single component but a group of parts working together as a “power phase,” and a typical motherboard has multiple phases to share the electrical and thermal workload. The PWM controller is the brain of the whole system, telling the components how much voltage is needed at any given millisecond. The MOSFETs are the switches that rapidly turn the 12V power on and off to regulate the current. The chokes are coils that smooth the pulsating current from the MOSFETs into a steady current, while the capacitors store and release energy to maintain a stable voltage. The controller, MOSFETs, Chokes, and Capacitors all work together and make up your VRMs. VRM quality is important because, when dealing with significant voltage fluctuations and output (its job), a lot of heat is generated. And if you have a power-hungry processor like a flagship-class Intel Core Ultra or AMD Ryzen 9, the chips require a lot of power and places a lot of stress on the VRMs. Most motherboards have metal heatsinks on top to help remove the heat generated. If it gets too hot (the exact temperature varies by MOSFET, but is generally around 100 degrees Celsius), the CPU then automatically throttles to prevent damage, which can hurt your performance, and that's what we’re here to shed some light on. What makes VRMs better (or worse)? VRM quality varies widely by motherboard. Typically, your enthusiast-class chipsets (Z890, X870E) have the most capable power delivery components, followed by the mainstream chipsets (B860, B850) and budget-class (A620 for AMD, “H” series for Intel). On most enthusiast-class boards, you’ll see 80-110A MOSFETs, more phases, and robust heatsinks, while mai…