corrupted BIOS?

So i have bought optiplex 7010 2nd hand with 1 year guarantee and after a while i bought win 8.1 pro and performed a clean install (it has a win 7 pro sticker on it though). After which i downloaded all the drivers for win 8 from the dell support including the bios one. After installing everything i decided to install the bios update too. After which my logo from the bios screen disappeared and it started to take 30-40 seconds to boot bios and after that only 2-3 seconds to boot the windows. Something was seriously wrong so i ran diagnostics from the dell official site "My Dell" was the name and after it said everything was great i tried reinstalling the Bios update only and nothing changed the time it took to boot was again 30-40 seconds. So during the last boot sequence i pressed F12 instead of F2 to enter the bios setup and entered the boot up menu and chose to boot up with Uefi + security boot on and after which a screen with red letter came up i didn't read it and pressed ok and after that it turned off and i cant even start it now.

I tried both options for resetting the bios like removing the cmos battery for half and hour. Didn't do anything

after which i tried with switching the jumper from PSWD to RTCRST for half an hour than back on PSWD

and after the first power up it showed something really fast which i couldn't see  and the only thing i saw was "System Halted" at the bottom (the screen was with black background not blue)  after this again nothing when i try to power it up. The computer just turns on and off by itself and no video. Is there a way of repairing this or the bios is corrupt and the motherboard has to be changed. 

forgot to mention bios version before update was A05 and the update i installed was A16

 fixed... and sory i dont know to remove posts :( or if its even possible