I had the opportunity to compare the same build of Debian Linux running on two different NB10s. Both were otherwise identical (same RAM, disk, installation). The quad-core (N3510) unit arrived with BIOS 1.00, so it was possible to gather statistics on this unit with both the original BIOS, and the latest version at time of testing (1.20).
The full table of results is available in a Google Docs spreadsheet.
Summary of results:
- The quad-core unit uses no extra power at idle.
- BIOS version 1.20 uses approximately 200mW less power than BIOS version 1.00 in all states.
- With two CPU cores fully utilised and two idle, the dual- and quad- core units’ power consumption is almost identical.
- With a greater CPU load, the quad-core unit can use more power than the dual-core.
This in itself does not mean that, for a given use case, that the quad-core unit will have a shorter battery life. More CPU power can allow a given operation to complete, and the system (CPUs and disks) to return to idle state, more quickly.
- The difference between minimum and maximum screen brightness is 1.4W.
- These results are with all powertop suggestions enabled. These in total save about a watt – highly significant on a 5W computer.