If you only have a Windows PC and Android MiniPC but you would still like to try out Linux then simply download and unzip one of the following files appropriate to your MiniPC and write the image to an SD card using 'Win32 Disk Imager' on Windows. Once you have written the image just put the SD card into your MiniPC and turn on the power. If you are a Linux user and want to try out one of these images then just write it to an SD card using 'dd if=UNZIPPED_FILE_NAME of=/dev/sdX bs=4M' where 'X' is the disk name and 'UNZIPPED_FILE_NAME' is the file name.
I'm providing images for the following devices:
Minix Neo X7 - https://drive.google.com/file/d/0B99O3A0dDe67UnpXdTZYUjhOX1U
PQ Labs A350-SSD - https://drive.google.com/file/d/0B99O3A0dDe67bTJXM2VZaGtMT2c
Rikomagic MK802IV New (AP6210) - https://drive.google.com/file/d/0B99O3A0dDe67NmIyLTl4Z3ZFRmc
Rikomagic MK802IV Old (8188EU) - https://drive.google.com/file/d/0B99O3A0dDe67UjVGRG14aGVoLVE
Tronsmart T428 - https://drive.google.com/file/d/0B99O3A0dDe67bFJBSTFqSzlxMG8
Booting will give you a full Ubuntu 12.04 LTS desktop with Unity. It will not affect your installed software and there is no pre-requisite for a specific stock or custom ROM to be pre-installed. No 'flashing' is required as everything needed to boot is taken from the SD card so it will work even if the NAND is empty or the device is 'bricked'.
Just a reminder that the Linuxium user password is 'p' (without the quotes) and that a root password can be set by entering 'sudo su -' and then 'passwd root' in a terminal window. You can expand the file system to utilise the whole SD card by entering 'echo -e "d\nn\np\n1\n81921\n\nw" | sudo fdisk /dev/mmcblk0' then rebooting and entering 'sudo resize2fs /dev/mmcblk0p1' to complete the resizing and Mali hardware acceleration can be enabled by entering 'sudo mv /usr/lib/arm-linux-gnueabihf/mesa-egl /usr/lib/arm-linux-gnueabihf/xmesa-egl'.