M14x R2 Won't Boot Up

[AstralSparks]

Hello techinferno folks, I am having trouble with my m14x

title says it all, details :

I was using A13 unlocked bios from svl7 (credits to him for making awesome bios mod), and I changed the video settings in advanced tab menu

from 64MB pre allocated DVMT to 1024 MB DVMT, applied the settings and suddenly my M14x won't boot up just a 3 secs light on the keyboard nothing on the monitor (no bios) and then it turns off.

since the main cause is my settings in bios, I also remove the CMOS to normalize the bios settings (3 times, the third time was removed for 4 hours) and it didn't help at all.

I have tested on PC wether its CMOS related or not by removing CMOS battery on my PC, result was my PC still showing the BIOS. Conclusion : CMOS have nothing to do with this.

I assume my bios is bricked so I googled and found out that I can flash my bios with USB Flashdrive (formatted to FAT32) by downloading the BIOS and renaming to PALB0X64.fd

and stick to USB 2.0 Port press END while plug in the AC adapter, my fan went crazy but there is no beep sound whatsoever to indicate the flash process is running,

so I renamed the file to PALB0MEC.fd and M14R2.hdr <-- still no beeps at all. but the fan went crazy (I'm using A08 Unlocked BIOS to flash the laptop.)

That's it. hope someone can help me without changing the motherboard (no money at the moment)

P.S I'm not covered by warranty so calling dell won't help