Yes, it will void the warranty because it means installing the special developer edition firmware:https://www.archos.com/support/support_tech/updates_dev.html?country=gb&lang=en
....For ARCHOS Generation 8 devices only:
Important notices to be acknowledged before downloading and installing the SDE firmware:
Once the SDE firmware is installed on a device, this device will be watermarked and ARCHOS will be able to detect that this firmware has been installed once.
Installing the SDE firmware is considered by ARCHOS as a voiding of the warranty and ARCHOS declines all liability and responsibility for any issues resulting from the installation of this SDE firmware.
ARCHOS strongly advises that only experts in embedded software development should install this firmware.
This firmware is provided "as is" and is not supported by ARCHOS.....