hello all ok i have the same tablet arnovo 7k g3 stuck on boot screen. i have read the thread and have gotten most of the same results so far still not able to load any type of file. well not exactly in one mode i was able to put image on hard drive only thing no way to execute it and if i removed the usb cable then reinserted it the file on the drive was gone.

in my experimenting i found since i had to re solder the usb port back on the board that the device uses a 5 pin connector with this name configuration. 

most usb cables come with pin 4 not connected maybe programming cable is different

i tested voltage on pin 4 and found it to be 1.4 volts above ground. i read that some manufactures use it pinned to gnd to identify master slave. so maybe using this pin ground might be able to flash the vimimicro chipset. 

one question i have anyone with the child pad taken any pictures of the main board both sides to see if we all have the same board with the same problems. just a thought.

i downloaded a tool called SDPack Tool which a program called vortexflash supposed to work with vimicro chips will test post results and any files if any success.

also i found that there is a jtag pad on the board so that is also a way once a method is found. from past experience jataging will work to replace the firmware.

i just read that the vimicro vc0882 chip is a cortex a8 cpu.  don't know true that is going to find out though.