Single CPU in Dual socket motherboards and PCIe slots

[chinesestunna]

Hi folks,

In the process of planning out my next build, I have a E5-2670 left over from last year and getting a Supermicro X9DRD-7LN4F to run it. I know from the block diagrams that only 3 of the PCIe slots will be available for access with a single CPU, but will the blank ones be at least powered? I have an Intel SAS expander which can draw power from PCIe (doesn't use the signal of course) so I just need it powered. Figure I use one of the CPU2 slots so to save on the slots with actual signal for more useful things.

Let me know if you have experience with this, thank you!

 

[Tha_14]

Hi folks,

In the process of planning out my next build, I have a E5-2670 left over from last year and getting a Supermicro X9DRD-7LN4F to run it. I know from the block diagrams that only 3 of the PCIe slots will be available for access with a single CPU, but will the blank ones be at least powered? I have an Intel SAS expander which can draw power from PCIe (doesn't use the signal of course) so I just need it powered. Figure I use one of the CPU2 slots so to save on the slots with actual signal for more useful things.

Let me know if you have experience with this, thank you!

My experience with consumer motherboards is that power is always available on pci/pcie slots. I would guess that it would be the same for a server board aswell unless there is some power saving feature where the 12v is not supplied until there is a load on the 5v of the pcie. My honest guess is that power would be supplied to those pcie slots. Good luck with your build!

 

[chinesestunna]

Thanks @Tha_14 I've went ahead and tested, power is going to the disabled slots Also another tidbit, Supermicro's manual was wrong (surprise surprise), on the manual it states CPU1 is main and provides PCIe slots 1,2,6 while CPU2 provides 3,4 and 5. First slot I tested was slot 2 and thought something was wrong with my processor or motherboard... I went through and tested every slot and turns out CPU1 provides 1,5,6, so slot 2 should actually mapped to CPU2

 

[Tha_14]

Thanks @Tha_14 I've went ahead and tested, power is going to the disabled slots Also another tidbit, Supermicro's manual was wrong (surprise surprise), on the manual it states CPU1 is main and provides PCIe slots 1,2,6 while CPU2 provides 3,4 and 5. First slot I tested was slot 2 and thought something was wrong with my processor or motherboard... I went through and tested every slot and turns out CPU1 provides 1,5,6, so slot 2 should actually mapped to CPU2

That's good. Happy it works for you. Enjoy!