Search for X570 motherboards that support a split design, ideally full ATX or bigger form factors.
Search for X570 motherboards that support a split design, ideally full ATX or bigger form factors.
Similar to the name, I'm searching for a full ATX X570 motherboard that allows bifurcation. Specifically, I need a model with at least two x16 PCIe slots capable of supporting 8x8 or 8x4x4 setups, plus a minimum of two M.4 PCIe Gen 4 slots that don't share bandwidth with any SATA ports. My main goal is to install two NVMe SSDs in the second graphics slot, which requires bifurcation so those extra drives can run at full 4.0 mode. This capability has been available on Intel chipsets for years and is one reason I remain a strong contender for my next build. If any AMD board can offer this feature, it would change things entirely. I’m certain the X570 supports bifurcation, but after reviewing many Asus datasheets, I haven’t found any that meet this need. In fact, most Asus boards don’t support 8x8 GPU/SSD configurations on X570—they only provide 8x4 options (on Prime and Crosshair boards). Do you know anyone who has experience with this feature? I usually go to Asus for my motherboards, but if someone else has it, I might reconsider.
I understand the Gigabyte X570 Aorus Pro supports SLI with AM4 boards but only if they have fewer than 1 M.2 slots. I filtered the list using PCPP to exclude unsupported models and checked if disabling SATA ports affected performance when running two SSDs at full speed. The Ryzen CPUs provide four lanes directly to M.2 slots, which is sufficient for high-speed operation regardless of board design. This setup allows adding a full PCIe 4 slot via the chipset. Unless you specifically need CPU lanes for GPU and SSD access, the Gigabyte B550 Aorus Master stands out as the best option. It supports eight GPUs, multiple M.2 slots, or sixteen with four M.2 ports.
I recognize this requirement, though I need a slot capable of handling four M.2 NVMe drives. That means two from the mainboard native M.2 port and two in a split design connected directly to the second GPU slot. On most Ryzen boards, the second GPU slot operates at 4.0 speed, which limits me to either a single NVMe at 4.0 or two at 2.0—something I’d prefer to avoid. For the Intel Z490 RoG Strix, I found three x16 PCIe bifurcated slots plus an additional M.2 slot running at 4.0, which doesn’t share bandwidth with SATA, allowing up to five NVMe drives. On AMD, I’m looking for a board that provides comparable SSD support. I haven’t explored this thoroughly yet, but I’m aware that most X570 boards, even high-end models with three GPU slots, typically lack the split design needed for flexible SSD mounting.
You require a board with PCIe x16 connectivity regardless of processor choice—whether Ryzen or Intel. This means you must use components like HEDT modules, X299 TRX40, etc., because the available lanes are insufficient for a GPU. I advised searching for SLI-compatible boards since they provide the necessary expansion. You'll need at least eight dedicated slots to enable SLI, which requires each slot to support splitting into multiple channels. Intel’s offerings only give 16 PCIe lanes from the CPU and just four to the chipset on LGA1200 (since then). All M.2 ports connect directly to the chipset, while the Z490 supports only PCIe 3.0 x4, even with upcoming 11th-gen CPUs that might use PCIe 4. In the Z490-E model, the manual confirms two x16 slots for full PCIe splitting and the third x16 plus the x1 slots link to the chipset. The Asus X570 WS features a PLX chip delivering up to four PCIe 4.0 x8 connections per slot, though these are combined rather than separate. Intel W480 boards can achieve similar performance, but this particular chipset doesn’t allow overclocking.
I confirmed the datasheet again and it looks like the Z490 only supports a single M.2 with both GPU slots and fully populated SATA (though this means they have roughly the same PCIe lanes as the X570, which seems to be the case). The X570 WS doesn’t offer bifurcation, even though it provides several x8 PCIe slots, none of which can accommodate four 4x4 bays.
Do you know what 4x4 refers to? It doesn’t mean connecting two NVMe drives in two separate x4 slots. It means using a single adapter card with two NVMe drives, plugging it into an x8 NVMe port and letting the computer treat them as two 4.0 mode SSDs. SSDs only reach their full speed in 4.0 mode; they don’t get faster in 8.0 mode. That means using an x8 PCIe slot is just wasting that lane. A split allows the x8 slot to accept two SSDs simultaneously, effectively doubling the capacity and boosting performance. I currently use a PCIe M.2 adapter that lets me mount two SSDs at once, so without a split I’d need extra cards for more drives. Each PCIe lane also has unused space, but those can’t be used for additional NVMe drives because they can’t be split and won’t recognize the extra ones I’ve already connected.
The difference lies in how SSDs are handled on various systems. Intel boards support multiple SSDs with PCIe x16_2 and x3 interfaces, each capped at eight channels of bandwidth. It seems some people might be confused about the capabilities of newer standards like PCIe 4, which isn't available yet.
yeah? well this is what written on Samsung EVO website. And if are you seriously claim that PCIE gen 4 speed worth the upgrade over ever PCIE gen 3? People every where don't even consider it worth spending money over gen 3, leave alone a real usuable lanes for extra SSD. Look, I am looking for X570 that can do this bifurcation ok? I know for a fact that X570 chipset can do bifurcation and they have PCI lanes left over in some board that allow me to do a bifurcation. If you don't know any just say it, I am not looking for an opinion whether that worth it or not.
Sure? Samsung's understanding doesn't necessarily mean you're right. You're bringing up PCIe 4.0 early, but I already mentioned that the Asus X570 WS (and a few others) can handle bifurcation. Only the WS supports four SSDs while still providing maximum bandwidth from four PCIe lanes. The others are limited to three, which isn't enough based on what you described for the Prime and Crosshair boards. You could simply say you're not interested in what I'm saying and move forward—this is ultimately your issue, not mine. It feels like I've spent money on an HP EX920 instead of SATA SSDs.