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Energy Efficient Hardware Investigated

CPUs - Intel

Test Setup

    Intel
  • Asus Maximus III Extreme (P55, 0309 BIOS)
    Common Components
  • 4GB OCZ DDR3 PC3-15000 / 1,866MHz / Platinum Edition @ SPD: 1,333MHz, CL7
  • 650W Seasonic X-Series PSU
  • 1TB Seagate Barracuda 7200.12 HDD
  • ATI Radeon HD 5770 1GB
  • ATI Catalyst 10.1 WHQL
  • Windows 7 Home Premium x64
Energy Efficient Hardware Investigated Intel CPUs
Click to enlarge

CPUs: Intel

CustomPC Benchmark

  • 95W TDP: Intel Core i7 870
  • 95W TDP: Intel Core i5 750
  • 73W TDP: Intel Core i3 530
    • 1601
    • 77
    • 193
    • 1488
    • 78
    • 158
    • 1175
    • 80
    • 116
0
250
500
750
1000
1250
1500
1750
Score and Watts (higher is better)
  • CustomPC Overall Score (points)
  • Idle (Watt)
  • Load (Watt)

CPU Power Efficiency Factor: Intel

CustomPC Benchmark / System load power use

  • 73W TDP: Intel Core i3 530
  • 95W TDP: Intel Core i5 750
  • 95W TDP: Intel Core i7 870
  • 10.13
  • 9.42
  • 8.30
0
3
5.5
8
10.5
Sorted by Efficiency

Intel's technological advantage is clear here, with efficiency factors for LGA1156 chips starting at 8.3, thanks to far higher overall CPC benchmark scores. Quite clearly the ball is in a whole different court compared to AMD. Despite the Core i5-750 and Core i7-870 both being '95W' TDP parts, the i5-750 system requires 35W less under load to complete the tasks. The Core i3-530 is rated at 73W but requires 42W less - but bear in mind its TDP takes into account the GMA HD graphics portion which we weren't using.

The Core i3-530 has the winning combination of not only being faster than AMD's cheap quad-core Athlon II X4 635s, but also only using 75 per cent of the power, so it generates a leading efficiency factor of over 10. The factor drops quite consistently as we look through the Intel range, although the i5-750 comes close at 9.42, and then the i7-870 again drops a point to 8.30.

It just goes to show how good Intel's 32nm parts are - despite the fact the Core i3-530 can never power down the 45nm GMA HD within the CPU package, because it also includes the PCI-Express and memory controller.