Intel 11th Gen mobo with 2 PCIE 3.0 x8 and 1 x4 nvme

[benjii]

I want to use an i5-11400 in a server, I'd like to use all 20 PCIE lanes and have 2 HBA cards at PCIE 3.0 x8 each and one NVME at x4. However, despite this being supported by 11th gen CPUs, all the motherboards I'm looking at only seem to offer 1 x16 and 1 x4 if you want to use 2 PCIE slots.

I understand the B560 chipset only supports 12 lanes, but the H570 supports 20 and the Z590 supports 24.

Am I completely misreading the spec sheets or are these features missing?

 

[doc]

11th gen has 20 CPU lanes and most motherboard manufacturers are simply creating a PCIE 4 bus with x16 slot and one 4 lane m.2.

There's something I'm doing that might suit your needs with the Gigabyte Z590 Aorus Pro AX. This board has the same setup as above, but the x16 slot can run at x8 and then it supports two more PCIE 4 m.2 slots. So you could have 3 PCIE4 m.2 slots and one x8 slot. That might be an alternative setup?

 

[Journey]

Am I completely misreading the spec sheets or are these features missing?

You'll need to look at a Z590 board as a minimum to get what you need as I said in the other CPU thread.

There are very few boards that officially support having the 8x/8x split from the CPU, only the high-end boards seem to have this and an option e.g the ASRock Z590 Taichi does this, and keeps the 4x PCI-E 4.0 for the M.2 from the CPU as well.

Using chipset lanes is a bad idea as they are on a shared link, not real lanes, just a way back to the CPU. If you saturated the devices then you'll get severe bottlenecking due to the shared bandwidth, so the only option is to split the main slots into 8x/8x, and then use the chipset lanes for the other devices that are maybe less important to you.

 

[benjii]

Yeah, I am having a look at higher end Z590s now. Thank you both for your input.