I was thinking about Supermicro SLG3-2E4R SLG3-4E4T, SLG4-4E4T or generic equivalents, but that's not going to work in a SFF chassis.
U.2 to PCIe Low profile adapter
- Thread starter compuwizz
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It likely doesn't matter. A 2.5" drive installed in such a way that it barely touches the top of the PCIe slot will extend about 4mm above the top of the low profile bracket.
If you have that much room, then it might work, but otherwise it won't fit.
Supermicro SLGx devices tend to require Supermicro board to operate. There are several threads here and other places, where the Supermicro Retimers/Redrivers do not work on non-SMC motherboards as they require special functionality in the BIOS to operate.
I'd search before jumping on those.
A relatively cheap option is C-Payne adapters (if in EU) or Micro Sata Cables in USA - they have m.2 slot redrivers (amazon link), PCIe slot ones and could ship to EU.
I received the adapters and they fit in the P3 Ultra. Will try the P350 Tiny shortly.
Hi,
I am also interested in this adapter. I have a Minisforum MS-02 where the slot is vertically oriented. So it is important how much the card sticks above the slot bracket. For me it looks like about 10 mm, which is probably to much for my case.
Did you measure the exact height above the bracket top?
How does the setup look mit the disk installed? Is it going higher than the card itself?
Thank you
Emil
I have currently an extension with the following parts from Amazon and it works fine with Gen4:
1x PCIe to SFF-8654 external:
cablecc 74-pin external Dual Slimline SFF-8654 8X to PCIE4.0
2x Cable SFF-8654 to MCIO:
10Gtek SlimSAS SFF-8654 to MCIO SFF-TA-1016 8i Cable, Mini Cool Edge IO, Straight, PCIe4.0, 85-ohm, 1-m(3.3ft)
1x MCIO to 2x PCIe Gen5 x16/x8 slot:
KALEA-INFORMATIQUE Riser-Adapter 2X MCIO 8i zu PCIe Gen 5.0 as extension to dual x8/x16 slots
1x PCIe to Dual U.2:
PCIe Gen4 x8 to Dual U.2 card
One slot is used for the dual U.2 card and the other slot by an LSI HBA 7305-16e. The last was previously in the PCIe Gen5 x16 slot in the MS-02 and used only half of the lanes.
With this setup I get about 11 GB/s on fio read from a pair of Samsung 9A3 Gen4 7.68TB drives with ZFS mirror/raidz1.
root@pve:~# fio --name=seqread4 --directory=/tank/test --size=128G --bs=1M --rw=read --ioengine=io_uring --direct=1 --iodepth=128 --numjobs=4 --group_reporting
seqread4: (g=0): rw=read, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=io_uring, iodepth=128
...
fio-3.39
Starting 4 processes
Jobs: 4 (f=4): [R(4)][100.0%][r=10.9GiB/s][r=11.2k IOPS][eta 00m:00s]
seqread4: (groupid=0, jobs=4): err= 0: pid=90487: Sat Apr 4 10:14:02 2026
read: IOPS=11.3k, BW=11.1GiB/s (11.9GB/s)(512GiB/46282msec)
slat (nsec): min=190, max=50510, avg=829.09, stdev=800.16
clat (usec): min=708, max=91708, avg=45186.70, stdev=2708.01
lat (usec): min=739, max=91709, avg=45187.53, stdev=2707.99
clat percentiles (usec):
| 1.00th=[40109], 5.00th=[41681], 10.00th=[42206], 20.00th=[43254],
| 30.00th=[43779], 40.00th=[44303], 50.00th=[44827], 60.00th=[45351],
| 70.00th=[46400], 80.00th=[46924], 90.00th=[48497], 95.00th=[49546],
| 99.00th=[52167], 99.50th=[53740], 99.90th=[57410], 99.95th=[66847],
| 99.99th=[84411]
bw ( MiB/s): min=10824, max=11968, per=100.00%, avg=11332.72, stdev=55.59, samples=368
iops : min=10824, max=11968, avg=11332.72, stdev=55.59, samples=368
lat (usec) : 750=0.01%, 1000=0.01%
lat (msec) : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.02%, 50=96.25%
lat (msec) : 100=3.71%
cpu : usr=0.48%, sys=1.02%, ctx=955994, majf=0, minf=23
IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.1%
issued rwts: total=524288,0,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=128
Run status group 0 (all jobs):
READ: bw=11.1GiB/s (11.9GB/s), 11.1GiB/s-11.1GiB/s (11.9GB/s-11.9GB/s), io=512GiB (550GB), run=46282-46282msec
All my 10x 3.5" HDD and 16x 2.5" SATA/SAS SSD disks are housed in a Fractal Design Define 7 XL used as DAS.
It has been modified and extended further since this post.
As posted before, I would like to relocate the U.2 disks into the MS-02 case with two PCIe Gen4 x4 slots, and use them as main system disks and for VMs and LXCs in Proxmox. The quad NVMe card with PLX88024 multiplexer occupying one of the x4 slots will then move to the x8 slot occupied by the the dual U.2 card now. This will improve performance considerably. Currently Proxmox uses a pair of Gen3 consumer NVMe drives for system and VMs/LXCs. Using the U.2 drives will give this a boost. And the quad NVMe card with further VMs will also have twice the bandwidth compared to before.
I then have a clear data separation between the MS-02 and the Define 7 XL DAS that allows a better occasional mobile use of the MS-02.
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Hi Emil,
I put a few more pictures on my blog post for the P3 Ultra here:
I hope these help you.
Regards,
VInce