I have one of these 4 u.2 to pcie cards and it rocks. I am recommending one of these to you based on your OP.
Couple of caveats.
#1 It is LONG... Make sure you have a case to fit. The sata power adapter is on the end so consider that clearance need as well. I used a 90* connector on mine in my full tower case and it barely fit.
#2 mobo must support bifurcation 4x4x4x4 to use all 4 ports. I believe you can use a dual port adapter if your mobo does not support that level of bifurcation.
#3 Consider airflow U.2 drives generate heat and you want it to leave the drive as to not thermal throttle under load.
Side note, my epyc mobo powered the card and 3 drives without attaching the end sata power connector. I did get the 4th drive and at the same time of installation, added the sata power connector to avoid any power to drive weirdness when they get under load.
This riser is pcie gen 4 though my p4510's are pcie gen 3
Only when your motherboard has PCIe signal splitting function, multiple hard drives can be recognized. Riser Card. 1 x Riser card. Support four disks, stable without losing disks. PCIE4.0 Card Slot Compatible: Support the use of motherboards with ×16 card slot interface.
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