Power, Heat, Efficiency And Overclocking
ASRock’s Z97 Extreme9 has the greatest number of on-board devices, yet its higher power consumption only occurs when it's under load. MSI’s Z97 MPower Max AC demonstrates lower power consumption across the board, though its 2W radio wasn’t active during this test.
The result is a 4.7% efficiency loss for the Z97 Extreme9 and a 6% gain for the Z97 MPower Max AC, when comparing the average of all three boards.
| BIOS Frequency and Voltage settings (for overclocking) | |||
|---|---|---|---|
| Row 0 - Cell 0 | ASRock Z97 Extreme9 | Gigabyte Z97X-Gaming GT | MSI Z97- MPower Max AC |
| Base Clock | 90-300MHz (0.1MHz) | 80-266.66MHz (0.01MHz) | 90-300MHz (0.05MHz) |
| CPU Multiplier | 8x-120x (1x) | 8-80x (1x) | 8-80x (1x) |
| DRAM Data Rates | 800-4000 (200/266.6MHz) | 800-2933 (200/266.6MHz) | 800-3200 (200/266.6MHz) |
| CPU Vcore | 0.80-2.00V (1mV) | 0.50-1.80V (1mV) | 0.80-2.10V (1mV) |
| VCCIN | 1.20-2.30V (10mV) | 1.00-2.40V (10mV) | 1.20-3.04V (1mV) |
| PCH Voltage | 0.98-1.32V (5mV) | 0.65-1.30V (5mV) | 0.70-2.32V (10mV) |
| DRAM Voltage | 1.17-1.80V (5mV) | 1.15-2.10V (5mV) | 0.24-2.77V (10mV) |
| CAS Latency | 4-15 Cycles | 5-15 Cycles | 4-15 Cycles |
| tRCD | 3-20 Cycles | 4-31 Cycles | 4-31 Cycles |
| tRP | 4-15 Cycles | 4-31 Cycles | 4-31 Cycles |
| tRAS | 9-63 Cycles | 5-63 Cycles | 9-63 Cycles |
None of the motherboards in today’s round-up push this particular Core i7-4790K to 4.6GHz, and higher voltage levels eventually cause thermal throttling. Differences between 1.278 and 1.283V can determine whether a board reaches an extra 1MHz base clock, so we’re treating the CPU O/C race as a tie.
XMP doesn’t specify every single timing adjustment that these boards are capable of setting, and some boards have looser tertiary timings to help achieve better overclocks. We started testing DDR3-2800 bandwidth after discovering poor performance on a different motherboard at this frequency. Though we don’t seen any that level of performance deficiency in these three boards, we’re still surprised to see MSI’s Z97 MPower Max AC fall slightly behind.
