LENOVO IDEAPAD U550 ACPI BSOD PROBLEM

[deviano]

Having problem with this laptop-cannot boot existing win7 os or install the other one. Always get bsod A5 --
the BIOS in the system is not fully ACPI compliant


Lenovo Ideapad U550
bios version INSYDEH20 23CN21WW
KBC version 03.22

After some researching, i get to this point:
-at lenovo support page there is NO bios update for this laptop or any other bios---weird 
-also know that the existing laptop came with win7 home premium os preinstaled, so the strange thing is that now can not be instaled or run
-with setting existing bios to default, no success
-through hirens usb i back up my bios with universal bios backup toolkit, and with rw portable i get rw file--not sure that the results from that are true
-i think i need mod for this bios and i need help with it--i understand that must be done with Phoenixtool256 but not sure to do it (having fear that i might brick the laptop with that)
- also think that the problem with this bios is that is acpi 2.0 (guessing i need 2.1)
-thanks in advance