- Please note: From a software point of view ODROID C1, C1+ and C0 are (nearly) identical. For Hardware differences between C1 and C1+ and to see how to use USB OTG on the latter please see [here](https://odroid.com/dokuwiki/doku.php?id=en:c1_hardware#c1_has_below_improvements_from_the_original_c1). C0 is a stripped down and more power efficient C1+ that can be battery powered (see here [how to read out battery voltage](https://odroid.com/dokuwiki/doku.php?id=en:c0_read_battery_voltage))
- Comprehensive device information and various tips&tricks can be found in [Hardkernel's wiki](https://odroid.com/dokuwiki/doku.php?id=en:odroid-c1). Please be aware that some of the information does not apply to Armbian (eg. we use a different partition table). Schematics can be found [here](https://dn.odroid.com/S805/Schematics/).
- Idle consumption of an ODROID-C1+ with Armbian defaults varies between 1800 mW (@504 MHz) and 1900 mW (@1728 MHz -- temperature also differs just by 2°C -- for reasons please refer to the ['race to idle' concept](https://en.wikipedia.org/wiki/Dynamic_frequency_scaling#Performance_impact).
- By defining `setenv hdmioutput "0"` and `setenv vpu "0"` in `/boot/boot.ini` followed by a reboot you get true headless mode (no consumption savings but `MemTotal` increases from 804 MB to 941 MB -- check `/proc/meminfo` if in doubt)
- You can save at least 170mW by cutting power to the internal USB hub (and also all USB devices connected to any of the type A receptacles) using `/sys/class/gpio/gpio4` (see description [here](https://forum.odroid.com/viewtopic.php?f=112&t=23763#p160852)). The same way you have full control over power consumption of a connected host powered USB disk: `umount /mnt/usb && echo 0 >/sys/class/gpio/gpio4/value` and `echo 1 >/sys/class/gpio/gpio4/value && sleep 2 && mount /mnt/usb`
- Interestingly at least on C1+ consumption remains the same if you switch from Gbit to Fast Ethernet or disable Ethernet at all. It seems the GbE PHY is powered all the time (maybe related to [performance/stabiity problems on ODROID-C1 in early 2015](https://forum.odroid.com/viewtopic.php?f=115&t=8121))
- Ethernet performance is ~940 Mbits/sec in TX direction and 400-500 Mbits/sec in RX direction. You might be able to tweak the latter a little, just have a look in the link one paragraph above.
- the red led is a power led while the blue led is custom. Boot stage: as soon as u-boot is loaded the blue led lights solid and when kernel starts this changes to `heartbeat` blinking with default settings. Check `cat /sys/class/leds/*blue*/trigger` for other functionality.
