Minisforum N5 (pcie to M.2 adaptor) no bifurcation?

[Enquiries]

Hi, I just received my N5 and really wanted more than 2 M.2 drives, so purchased this adaptor
https://www.amazon.co.uk/dp/B0BHWN7WKD

but alas, I can only see 1 of the drives on there. Any suggestions for a card that works, at least 2 more M.2 drives.

Many thanks.

[ed]

Thanks for your message. You’re absolutely right to suspect bifurcation as the issue here. The Minisforum N5, like most compact systems using mobile or embedded chipsets, does not support PCIe lane bifurcation in the BIOS. This means that cards like the GLOTRENDS PA41, which require the motherboard to split a x16 or x8 slot into multiple x4 lanes, won’t be able to expose more than one of the M.2 drives. Only the first slot (NVMe-1) gets picked up by the system, which is exactly what you’re seeing.

If you’re looking to expand beyond the built-in M.2 slots without relying on bifurcation, your best option would be to go for a PCIe switch-based adapter rather than one that relies on the motherboard’s bifurcation support. These cards have an onboard chip (usually from ASMedia or PLX) that handles the multiplexing of lanes internally, presenting multiple drives to the OS through a single x4 or x8 connection without needing BIOS support for bifurcation.

There are a couple of switch-based cards on the market that will do what you’re after. The downside is that they tend to be more expensive—often around £100 or more—and may get warm under sustained use. Look for cards using the ASMedia ASM2824 or similar chipsets. One example to look at is the IOCREST SI-PEX40152 or similar variants from SilverStone or SuperMicro that explicitly state support for non-bifurcation systems. They tend to present all drives as separate PCIe devices even on platforms like the N5.

Just make sure your power supply can handle it and that the case has enough cooling, as these cards can add heat. Also, the NVMe drives you install will all share the single upstream PCIe link, so while you can access multiple drives at once, total throughput will still be limited to what the host PCIe lane can provide (likely PCIe 3.0 x4 on the N5).