Rampage VI Extreme M.2 slots

[willdearborn]

Can someone give me a definitive answer as to how each of the 3 M.2 slots are wired on the RVIE? As in exactly which are CPU and PCH? It looks like the DIMM.2 has one each CPU and PCH but what about the 3rd slot down at the bottom? Is that CPU or PCH?

My goal is to use 2x M.2's (1xCPU for boot drive and 1xPCH for optane accelerator) while keeping PCIe x8_4 at full x8 bandwidth.

Can I use one of the DIMM.2 slots and M.2 socket 3 for this purpose and still have x8 on PCIe x8_4?

EDIT: I forgot to mention I will be using a 44 lane CPU and will also be using SLI @ x16 and x16

[feedmeink]

The manual will explain which m.2 slot uses which controller.

[willdearborn]

The manual will explain which m.2 slot uses which controller.

Unfortunately it does not. At least not that I can see. No where does it give the source of M.2 socket 3. I believe it is probably PCH but I would like confirmation.

But thanks so much for your detailed and helpful answer!

[feedmeink]

I have the same mobo. It lists it, but I'm at work. I'll look it up for you when I get back

[feedmeink]

Looked up the manual online. The dimm.2 slot shares the cpu. The one under the cover shares pcie slots. For refrence go to page 1-28 and 1-29. You may have been looking up m.2 installation page. The dimm.2 mentions pch. If you look up the definition for pch, it appears to share with cpu. Hope this helps. Hope it's enough detail.

[aron123]

Can someone give me a definitive answer as to how each of the 3 M.2 slots are wired on the RVIE? As in exactly which are CPU and PCH? It looks like the DIMM.2 has one each CPU and PCH but what about the 3rd slot down at the bottom? Is that CPU or PCH?

My goal is to use 2x M.2's (1xCPU for boot drive and 1xPCH for optane accelerator) while keeping PCIe x8_4 at full x8 bandwidth.

Can I use one of the DIMM.2 slots and M.2 socket 3 for this purpose and still have x8 on PCIe x8_4?

EDIT: I forgot to mention I will be using a 44 lane CPU and will also be using SLI @ x16 and x16

The M2 slot beneath the heatsink is connected to the PCH. This leaves us with two slots on the DIMM.2 card: the first one (M2.1 on DIMM.2) is either connected directly to the CPU (in which case it shares bandwidth with the U2 connector, so you can't use both), or to the PCH (in this case you can still use U.2, but the 4x PCI Express slot coming from the PCH, the shortest one in the middle of the board, is disabled). The M2.2 slot on the DIMM.2 card is either disabled, or it cuts into 4 CPU lanes of the bottom PCI Express slot (it will operate in 4x mode, not in 8x mode).

So for your case, place your Optane drive to the M.2 slot in the middle of the board and the other drive to M2.1 on the DIMM.2 card and make sure in the BIOS it gets connected to the CPU.

[BigJohnny]

Simply put the inboard M2 on the DIMM.2 (closest to memory) can be set for PCH or CPU. All others are PCH only.

[Neosabre]

Is it best to run my Samsung 970 Pro M2 NVMe drive through the CPU or PCH?