I tried this 3.06 version (used the win flash provided with the .rar file in the link) and it bricked my board. I originally had a 3.06, but foolish me updated to 3.10 from HP's site as I was new to what a BIOS was. I originally wanted to OC after installing a new video card, and felt my CPU was holding me back. After learning some basics to OCing, I found out HP blocked the settings, so off to learn about different bios LOL. So, the learn to crawl before walking applies 0_o. Anyways, I was unsuccessful at downgrading to a 3.06 with the unlocked features using the supplied winflash program.
After some study of the unlocked 3.06 file in WinHEX, it seems some of the file might be corrupt, or it might be the nature of modding the version of that BIOS, as there were a bunch of commands that were FF FF FF FF FF. Anyways, if you stumble to this link like I did, I suggest making a PROPER BACKUP on a USB (make sure you can boot to a USB 1st
with your current BIOS. Read thoroughly about how to restore a bricked board before trying to flash your BIOS. Had I followed this advice, I wouldn't be writing this LOL.