which bios is the latest for duox2 having looked through the modchip forum i cannot find out which bios to use as some topics are over a few years old can anyone point to the correct one

Use 512 kb bioses and i believe that the most current are the X2 5035 and the evox m8+ which ever you prefer

You didn't look very hard. The last post in this section to answer this question wasn't a few years old, it was posted on August 2nd this year, and is three posts below yours.

It's X2.5035, the same as it has been for the last few years, since nobody is writing new BIOSes for the Xbox 1.