Best ASRock Motherboard for PCIe 5.0 SSD (7.68TB,

Hi ASRock community,

I?™m planning a high-performance workstation build around a PCIe 5.0 SSD (7.68TB, U.2 2.5") https://serverorbit.com/solid-state-drives-ssd/pci-e5-0-ssd/7-68tb-ri-2-5inch and need advice on motherboard compatibility. Key requirements:

PCIe 5.0 Lane Allocation:

Does the ASRock X670E Taichi fully support Gen5 x4 speeds on U.2 via M.2 adapter?

Concerned about shared bandwidth with GPU (planning RTX 4090 in top x16 slot).

Cooling Solutions:

Will the SSD?™s sustained 12,000+ MB/s writes throttle without active cooling?

Any experience with ASRock?™s included M.2 heatsinks for U.2 adapters?

Real-World Use Case:

Primary workload: 8K video editing (DaVinci Resolve) + RAID-0 scratch disk.

Secondary: Game library storage (to avoid frequent reinstalls).

Current shortlist:

X670E Taichi

Z790 Riptide (if Intel better handles Gen5 splits)

Budget: ~$400 for the board. Thanks for any insights!

Assuming you're going for Ryzen 7000 / 9000 or EPYC 4004 / 4005 (not out yet) series, the CPUs have total of 28 PCIe Gen.5 lanes.

4 of them are used to connect to the chipset, so you're left with 24.

16 for the main PCIe slot(s), either in x16 or x8/x8 as described in the motherboard spec.

4 for the main m.2 slot.

So technically, there's still 4 more lanes, but I don't see them being used based on AsRock's specification pages. I do wonder if there are other motherboards (not necessarily AsRock) that give you the main x16 PCIe slot + TWO m.2 x4 slots, all connected directly to the CPU. It should be possible, according to AMD's spec.

Either way, the main PCIe slot (x16) and the main m.2 slot (x4) are NOT sharing bandwidth. You should be fine.

You'll not be able to use the motherboard heatsink when using an m.2 -> u.2 adapter. It wouldn't make sense to install a "heatsink" anyway, because the adapter is just bunch of wires and a big connector. There's nothing in it to heat up.

As for SSD itself needing active cooling, that's a question for the SSD itself, not for AsRock.

Finally, regarding adapter compatibility, who knows? PCIe Gen.5 uses incredibly fast signals. You're hooking up an adapter with a long cable to the u.2 device. You're adding 2 additional connectors, compared to direct connect m.2 SSD, plus a long cable. These connectors and cables must be incredibly high quality to prevent degrading PCIe Gen.5 signals.