Hey Folks, I sorted out my issue from this morning and thought I would add the (embarrassing) solution here in case anyone else encounters it. I recently purchased a USB mechanical keyboard with an internal USB hub.  It has 2 USB connections (both 3.0, I found, when I RTM).  I hot-swapped the keyboard.  After a power-cycle (this morning), I encountered the "system board failure" diagnostic issue. Later, I pulled the USB cables out and the computer booted (immediately, with no further action on my part). I had plugged the keyboard USB cable into a USB 2.0 port and the hub USB cable into a USB 3.0 port.  Any combination that is not both USB 3.0 ports causes the "system board failure" diagnostic on my T3620 and prevents the system from booting. I hope this saves someone some time. Cheers
Hey Folks, This morning my Dell Precision 3620 MT is giving me an amber 2-1 pattern on the power button. According to this resource my motherboard is dead: [URL] The motherboard P/N is 0MWYPT (from the label under the circled 'Dell' on the motherboard).  I see some available used boards with this part number (ebay, etc.).  I also see some available boards with P/N 09WH54 that claim they are interchangeable. My questions are: 1) Am I correct in diagnosing the motherboard as the issue? 2) Is 09WH54 a valid replacement for 0MWYPT? (My system has the M.2 PCIe NVMe and a Xeon E3-1240 v5) 3) What should I check to ensure this doesn't happen again?  Should I check the voltage on the PSU?   Thanks for reading - any advice is welcome!
Precision 3620 MT System Board Failure / Replacement