NeoZeruel, I think you misunderstood me. I would like to downgrade my BIOS not VBIOS. Between BIOS and VBIOS is a difference. BIOS handles IO during the boot process, while VBIOS handles video related IO. Currently I am stuck on 3.05 but need 2.07 as described in step (3). The downgrade tool does not support dos mode. I've tried with win installation command prompt but this one didn't work as well.
Update:
I managed to downgrade my BIOS.
(My win installation is a 64 bit version. This might be the reason I couldn't use the program from step 3.)
What I did: (Notice: I do not recommend this to do on your own, unless some expert here confirm that this method is not dangerous!)
* I've extracted 74cn44ww.exe (Original BIOS Upgrade to 3.05)
* Removed Win305.bin and platform.ini
* Extracted Y510p-Y410p_v207_[stock].exe (BIOS downgrade tool to 2.07)
* Copied Y510p-Y410p_v207_[stock]/platform.ini and Y510p-Y410p_v207_[stock]/207stock.ti to 74cn44ww
* Called 74cn44ww/InsydeFlashx64.exe
* From here the downgrade mechanics started to rotate.
Update:
Finally upgraded to moded bios
And NeoZeruel, thank you for the link, I used that for vbios flash.