Charge 24 hours
No led (aside from charge led)?
Press and HOLD pwr button 30 seconds
Explicitly blank emmc, first 20M,, ie
dd if=/dev/zero of=/dev/emmc bs=1M count=20,,,,, /dev/emmc as appropriate, don't make a mistake
Try mrfixit's distro
Be sure SD cards are GOOD quality, 80-90% are crap
something like (upper right 4 numbers are what count)
sudo iozone -e -I -a -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -i 0 -i 1 -i 2
(within directory you wish to test)
No led (aside from charge led)?
Press and HOLD pwr button 30 seconds
Explicitly blank emmc, first 20M,, ie
dd if=/dev/zero of=/dev/emmc bs=1M count=20,,,,, /dev/emmc as appropriate, don't make a mistake
Try mrfixit's distro
Be sure SD cards are GOOD quality, 80-90% are crap
something like (upper right 4 numbers are what count)
sudo iozone -e -I -a -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -i 0 -i 1 -i 2
(within directory you wish to test)