XPS 17 L702X - after BIOS update won't boot, seems to be bricked.

Hi, I have an XPS 17" L702X which had the A12 BIOS. Since it is recommended (by Dell), I updated to the A19 BIOS. I followed the instructions to the letter, I am technically competent, I knew not to interrupt the process etc. etc.

So the laptop rebooted, the BIOS flashed, and now I am left with a machine that won't boot.

I switch on the power, the fans go on the, the power light goes on, the three icons above the keyboard next to the WAVES icon light up, and almost exactly 10 seconds later, the laptop powers down. There is no display or beep.

I have tried taking out the battery and AC, holding down power, then attaching the AC again, no help.

The laptop is no longer under warranty.

I'm pretty upset considering I was using DELL'S software and performing an update that they suggest. 

Can anyone help please? Thank you very much in advance.