Dell Precision T3610

Hi all , i just bought a Dell Precision T3610 last week , it came with 16GB ad 500GB HDD I add a SDD 100 GB to install ESX and when I changed Bios to UEFI safe boot , my computer got bricket/ Black screen ,

So far i try to : 

• no image for post , no dell logo
• it boots and start the numlock light on keyboard
• take off all SSD and HD,
• one memory
• Took off password reset switch on Motherboard for 10 seconds , no power connected 
• Changed monitor cables ,
• Nothing works so far, blank screen. 
• I tried power cycling and going to the BIOS via F12, but got the same result. 
• I tried F2 with the same result. 
• I unplugged the machine, pulled the battery
• held down the power button for 30 sec, waited 30 min before re-plugging the machine back in. 
•  
• The volatile portion of the BIOS should have been cleared.  I got the same result on re-boot except the computer powered itself off a couple of times before getting to blank screen 

At this point, the SSD is fully backed up so I am not in danger of losing data, but I can't get the machine to boot or go into the BIOS.   Also, I wasn't inside the machine for a few days before the original failure so it is unlikely I zapped anything.

The situation leaves me with a couple of questions.

1.  Does anything about UEFI allow the system to be put in a state that clearing the volatile portion of the BIOS doesn't return the computer to its default configuration?

2.  Any thoughts about how to get the computer back into its default configuration?

I have read all other post related to BIOS and Upgrades but is not the same . Before sending it to Dell , suggestions are welcome

thanks

Pablo .