Power Consumption and temperatures

Power Consumption and temperatures

The new C3 AM3 Phenom II X4 processors have an improved TDP (peak wattage); compared to the last flagship product AMD shaved off roughly 15 Watts while maintaining performance. For this review we use and test with the Phenom II X4 965BE (C3) processor that has a TDP of 125 Watts (= 125W peak, when all 4 cores in the processor are 100% utilized and stressed).
Much like the last-gen products, we have four active and independent cores here. Each core can be clocked down independently if not utilized, saving heaps of current. The C3 revision now indeed has C1E locked down. If the cores are temporarily inactive, they can pretty much put themselves in sleep-mode (clocking down). HyperTransport will power down and a low-power stage is activated on the memory.

This boils down to even better power management. Keywords here are improved power tuning with additional performance states.

As a result we notice our test platform peak out at roughly 165 Watts power consumption when we stress the CPU cores. Our system idles merely at 100 Watts. This is a complete PC with a high-end graphics card inserted.

This setup uses the MSI 785GM-E65 based AM3 motherboard to which we added a dedicated graphics card (Radeon HD 5870), you'll notice that the end-result overall in idle and peak wattage is very impressive.

As you can see, once we stress all four CPU cores with Prime95 (stress test), our power consumption maxes out at roughly 165 Watts.

Let's put the processor under heavy load and see how temperatures behave.

Here you are looking at a CPU stress test. Processor temperatures while 100% utilized remain below 45 Degrees C / 113 F. We are cooling the processor with a OCZ Vendetta heatpipe based cooler.