[NAME] It appears that the BIOS update bricked the motherboard. If the power went out during the BIOS update that could be the cause. If BIOS Recovery was enable in the BIOS you may be able to recover the BIOS. Here is the procedure: [URL] I have never done a BIOS recovery and since the XPS 8940 is new, I am not sure if this procedure works for this PC.
Hey all, We had a power outage a week ago and for some reason on restart the computer decided to do the bios update it had waiting. During that time the power went out again and after the computer will start up but nothing goes on the screen but the power will stay on.  Technical support thinks it is the motherboard in what i assume is the bios. The computer is out of the US and they offered to fix it but the computer has to be in the US. I have a motherboard on order from Dell but its been delayed over a week and my son uses this computer for school which starts again tomorrow.  I'm looking to see if there are any other options open. I have tried everything i can find.  As soon as the power plug is in the computer will start up and even holding down the power button to turn it off won't turn it off long. It waits about 2 seconds and starts up again.  Attempting an RTC/cmos reset by holding down the power button for 30 seconds makes the computer goes through what the walkthrough says, restarts and such but nothing ever happens after that. Power light and fans stay on but nothing on the screen/keyboard/mouse.  The keyboard lights only ever come on for about 4 seconds on some of the startups but pushing F2/F12 or anything else does nothing.  Removing the battery on the motherboard and draining remaining power also does nothing.  Thanks. Any other information that might be needed I can provide. 
XPS 8940, doesn't boot, lights stay on