Do Xeon CPU's in Dual Configuration Combine the max Number of PCI Express Lanes

[Goldstar Interactive]

Hello. I am building server with 2 Intel Xeon Processor E5-2697 v2 with 12 cores and 40 PCI Express Lanes. If I build a system with 2 of these processors, does that mean 80 available PCI Express Lanes?

I'm building it with the Asus Z10PE-D8 WS SSI EEB Dual-CPU LGA2011-3 Motherboard. Z10PE-D8 WS

Thank you for taking the time to read this.

 

[Barty1884]

Yes, dual-socket boards combine the lanes from each chip. 2x 40 lane chips= 80 lanes total.

 

[Goldstar Interactive]

Thank you for your speedy answer

 

[dgingeri]

Yes they do, but they can suffer from latency when crossing CPUs. Dell's R730 with dual processors has 3 x8 slots that attach to the second CPU, and my last company had some performance issues with SAS cards for external storage attached to those slots. They ended up switching things around and putting the FC VTL cards and 10Gb NIC there instead. (This was a backup appliance that my company bought, added cards and software, and then sold for 10 times the price.)

The number of PCIe lanes available depends entirely on the board. If the board has the capacity of using all 80 lanes, then that's what you'll get. From the slots I see available on that board, it looks like you have 66 lanes available if all slots are used. The downside is that those cards will need cooling. If the case isn't set up to push air through those cards when they're densely packed like that, you'll lose available lanes to putting cooling fans next to devices.

I, too, have been experimenting with things like this. I currently have a P9X79-E WS board for my server, with two Dell RAID cards, one internal H710 and one external H830, a Qlogic 10Gb NIC, an Intel 10Gb NIC for iSCSI, and a low end video card. (That's 40 lanes worth of devices.) Due to cooling concerns, it hasn't gone as well as I had hoped.

 

[kanewolf]

First that motherboard doesn't support V2 CPUs. See this page for the list of supported CPUs -- https://www.asus.com/us/Motherboards/Z10PED8_WS/HelpDesk_CPU/ V3 and V4 CPUs only.

Usually the PCIe lanes on each socket are mapped to specific slots on the motherboard (slots 1 - 3 might be socket 1 and 4 - 6 might be socket 2 for instance).