The first computer is a typical office system. It is an inexpensive computer suitable for office applications:
- CPU: Intel Pentium Dual-Core E2220 (2.4GHz)
- CPU cooler: GlacialTech Igloo 5063 Silent (E) PP
- Fan: GlacialTech SilentBlade II GT9225-HDLA1
- Mainboard: Gigabyte GA-73PVM-S2 (nForce 7100 chipset)
- System memory: 1GB Samsung (PC6400, 800MHz, CL6)
- Hard disk drive: 160GB Hitachi Deskstar 7K1000.B HDT721016SLA380
- Optical drive: DVD±RW Optiarc AD-7201S
- Card-reader: Sony MRW620
- System case: IN-WIN EMR-018 (350W)
I installed Microsoft Windows Vista Home Premium SP1 (32-bit) and necessary drivers on the PC.
Let’s start with the very beginning: booting Windows up. The power consumption was being measured from the turning on of the computer to the loading of the Desktop.
As you can see, this configuration has an extremely modest appetite. The current is no higher than 3 amperes on any of the lines. The CPU behaves in an interesting manner: its power consumption is high for the first 20 seconds (the X-axis of the diagram, showing tenths of a second) but then drops suddenly. This marks the moment the ACPI driver is loaded and enables the CPU’s integrated power-saving technologies. After that, the CPU’s power consumption increases above 12-15W only under load.
3DMark06 is obviously limited by the graphics core and cannot load the CPU fully: the latter remains in a reduced-consumption state most of the time. The power consumption grows up a little on the +3.3V line and just a little bit on the +5V line.
The integrated graphics core copes with the heaviest 3D FurMark test easily – in terms of power consumption, that is. Interestingly, the components all show stable consumption although the CPU is not loaded fully: it has a higher consumption at the beginning (the launch of the test) than in the middle of the diagram.
The CPU reaches its peak power consumption – as much as 3 amperes! – under Prime95 (the heaviest test called “In-place large FFTs”). I’m being ironic, of course.
There are no changes when FurMark and Prime95 are running simultaneously. The CPU is loaded fully whereas the integrated graphics core has low power consumption.
So, here are the results.
This computer will obviously do well with any power supply. Even 120W power supplies from mini-ITX cases will ensure a twofold reserve of wattage for such a configuration. The type of load does not affect the power consumption much because the CPU is always the most voracious component. If the 65nm Pentium Dual Core E2220 were replaced with a newer 45nm E5200, the system’s power draw would be a dozen watt lower.
The power consumption in sleep mode (Suspend-to-RAM) is a mere 0.5A (PSUs’ +5Vsb sources can yield 2.5-3 amperes).