X10SLL-F motherboard
I'm seeing on the VGA output a supermicro logo (in #s), with "IPMI Initializing..." at the bottom left, then "System Initializing...", then the number "15" at the bottom right of the display -- is this the POST code or some different status/error number from the BIOS?
Yes, the number on the bottom right corner of the screen is the BIOS post code.
Please check that your memory is ECC Un-Buffered memory (UDIMM)