For testing power consumption, we took our test system and plugged it into a Kill-A-Watt power meter. For idle numbers, we allowed the system to idle on the desktop for 15 minutes and took the reading. For load numbers we measured the peak wattage used by the system while running the OpenGL benchmark FurMark 1.10.1 at 1024×768 resolution. We also ran four game titles at 1920×1080 and averaged the peak results recorded the highest Wattage seen on the meter for the gaming results.
Power Consumption Results: When it comes to power use, we measured the entire system at the wall and discovered that the power draw greatly varied at load depending on what video card was in the system. The ASUS HD 7970 Matrix used the most power in at idle and in the games, but not in Furmark. ASUS recommends a 650W power supply for a system using this card and since we were pulling over 400 Watts at the wall with our test system this is likely a good suggestion. Keep in mind our test system has just one SSD and no system fans, so if you have extra hard drives and a ton of cooling fans you’ll likely be pulling more power than this.