First thing that i noticed after installig it was that eject button wasnt working (just like with broken 83850c). well thats ok i can open it manually to go vendor mode.
Step1: ok then i got the dummy(key) from it and tryed to spoof it to 83850C with new key, done.
Step2: i tryed to spoof newly created firmware (benq that thinks its 83850C with new key) with BenQ_ixtreme1.6. and
Step3: and write command sended wich was successfull... after restarting xbox it was still flashing green light and jungleflasher is not even recognizing my benq drive anymore..
used Jungleflasher.
was my spoofing logic right first to make BENQ look like 83850C with new key and then spoof it with benq_xtreme?
Hopefully my english is enaugh

UPDATE: tryed to flash my benq back to original over dos with IPREP009 with no luck it wont even recognize my drive anymore.
Writing ended with error. "No atapi drives presents"
now i got 2 drives that are not recognized

is it possible that it has something to do with my sata ports? i mean i successfully flashed two other 360's with same computer + succesfully flashed that new benq drive (just died after flashing

even disconnect my sata HDD's and tested all sata ports without any luck, still strange if problem is with my sata...
Motherboard: Asus p5b, P965 chipsed wich has ICH8 sata ports?
Many thanks for your help.