it is are a original box bought almost when they first came out long before there was clone boxes
i think it was back in 2008
and if its was a clonebox i would newer asking here in the original boxes forum

i am struggling with the exact same problem
removed the tuner it boot fine if i plugin the tuner or a replace tuner
i just bought also rev j nothing happens only endless reboot
i have read trough other topics with a similar problem
but not found a solution what can it be