As I purchased this board secondhand, I'm not sure if this is an S2600CP2 or S2600CP4. There is a sticker that reads: PBA E99552-507 QSCP22002137
I have dual Xeon E5-2630L v2 CPUs, and I have 4 x 8GB 1333MHz DDR3 registered, ECC DIMMs on order.
While waiting for these DIMMs to arrive, I decided to test the board with some desktop DIMMs just to make sure that the board is in working order. My understanding is that this board will accept regular desktop DIMMs. According to the "Technical Product Specifications", this board is supposed to support UDIMMs. Unless, there's such a thing as unregistered server DIMMs, I'm assuming "UDIMMs" is the same as typical desktop DIMMs.
First, I tried to a single 4GB 1333Mhz DDR3 desktop DIMM and got the "Invalid DIMM population" on POST. My understanding is that a single DIMM configuration is supported. I tried this single DIMM in all 4 banks, and got this error each time.
Second, I tried various combinations of 4 x 8GB 1600Mhz DDR3 desktop DIMMs. I've used these DIMMs singly, in pairs, and all 4 at a time. I've tried filling both slots of 2 channels as well as single slots of 4 channels. I've tried a single DIMM in all 4 banks, observing the "farthest fill first" rule.
Another thing to note is that although the "Invalid DIMM population" error appears on the display during POST, the LED POST progress code does not indicate this. According to the specifications, this error SHOULD BE indicated by:
Lower Nibble LEDs (lit green): #0, #2, #3
Upper Nibble LEDs (lit amber): #5, #6, #7
However, in MY CASE, the LEDs are lit as follows:
Lower Nibble LEDs (lit green): #1, #2, #3
Upper Nibble LEDs (lit amber): #5, #6, #7
I don't even see this combination in the technical specifications.
Here is a video showing the POST progress LED sequence:
