Monday brought news of backups successfully booting on Xbox 360s with modified DVD firmware images. LittleJonny put together a tutorial on how to boot two different DVD drive firmwares. To perform this mod you need a second SST 39sf020a flashrom plus some resistors. The two flash chips are soldered directly on top of each other except for pin 15. Two wires are then attached. Which flash chip is used depends on which wire you pull to ground. Just add a switch and you can install a modified firmware on the second chip while keeping your original. I’m guessing Microsoft will put firmware detection into the dashboard to combat this, but this will keep your original firmware intact so you won’t have to reflash if something breaks.