I have a Allwinner Quadcore A33 1.2ghz 9" tablet with chipset astar-rtl8703 which I think I bricked. What I did: - tablet was infected with trojan/virus, impossible to remove by reset to factory settings (virus is in /system) - I rooted the tablet with Kingo Root - tried to remove virus with Lookout, Malware Bytes and Stubborn Trojan Killer. They failed. - tried to delete the virus with Titanium Backup. Unsuccesful. - used adb shell to manually mount the file system as writable and tried to manually delete the infected files from /system. Failed with message "Operation not permitted". - after restarting tablet it is now stuck with displaying text "android" in the middle of the screen. I didn't find the button/key combination for doing a hard-reset. Do you know which are ? Or where can I find a image of ROM and tools to flash the tablet again ? Thank you for your help.