5 Slot M.2 B-Key SATA Base SSD PCI-e 3.0 x2 Bandwidth Expansion Card Require x16 Slot SI-PEX40142

I purchased two of these boards. Each board has the option for two M.2 drives. They provide amazing performance on my older i7 board which only has PCIe 2.0a support. My previous M.2 board did not have the onboard chip which is apparently a PCIe lane "switch" which basically allows more use of the slot bus. The M.2 cards I installed are PCIe 3.0 x4 cards so on my old card this would translate to PCIe 2.0 x4 since the motherboard did not support PCIe 3.0. Due to the fact that each PCIe 3.0 "lane" is twice the speed of a PCIe 2.0 lane I would not get half the performance. The onboard "switch" processor allows use of more lanes and allows near PCIe 3.0 performance. Keep in mind that having two M.2's on one card mean they still share the slot bandwidth.Windows does not support booting from software created striped volumes and the cards don't have a RAID chip on them to create hardware RAID. Actually, I wish this card did support hardware RAID such as striped volumes, it would be a great feature.What I did is purchase two cards and placed four M.2's on them. I placed my C drive on one (Windows). Then I placed a smaller cheaper M.2 on the second card as extra storage because due to the PCIe "lane switching" placing only one M.2 on the card will cause lockups and system freezes. In slot two on both cards I place high speed 1TB M.2's and created a striped volume. Placing them on separate cards allow them to utilize separate "switch" processors to ensure maximum performance. Then I reinstalled Windows and interrupted the installation to set the Users and Program folders to my striped volume. Then on my first login, I moved the page file to my striped volume. Now I have maximum performance out of my two M.2's with a total 2 TB on the striped volume.Thus far the setup works great HDD access is amazingly fast and probably faster than anything the creators of this motherboard expected. Also, I created a large 50-100 GB swap file because the drive is really fast so paging does not provide a noticeable slow down and effectively gives me all the memory space I need. I typically just leave everything open and running allowing me to quickly return to things.Overall, if you are looking for the maximum performance out of your PCIe 3.0 M.2's this is THE card for you.Pros:- On a PCIe 2.0 system this is likely the fastest way to add an M.2 HDD- Allows extreme performance even on a PCIe 3.0 slot.- PCIe lane Switch processor allows nearly full use of the slot- M.2 Cooling features like thermal pads heat spreader and fan.- Allows two (or more) M.2's in one slot (a lot of other cheaper cards have one M.2 one slot)Cons:- Does not have hardware RAID, I realize this may require a different processor, but it is a big feature.- Requires both M.2 slots to be populated due the PCIe lane switching.- While the SATA hard drive interface comes on the motherboard this requires the purchase of a 200 dollar card.

Works as intended, I setup the SSDs as a striped drive using the windows utility

Installed in 2009 Mac Pro tower with 2 AData 512GB NVMe SSDs, planning to use one for Mac OS and the other for Windows 10 Pro. Initially worked great as speedy non-boot drives. Attempts to use as a Bootcamp drive for Windows 10 completed install but would not boot. As a Mac OS 10.13.16 High Sierra boot disk it would boot with significant delay, resulting in a slower boot time than my Sata SSD. Occasionally the system would refuse to boot. I'd have to use the startup option key and force boot from the Sata SSD. After 2 months, the drives disappeared from the desktop and then the machine would not boot if the card was installed. I separately tested the SSDs and they were fine. I am assuming it is broken - a waste of money.

I bought this for a Mid-2012 Mac Pro which has 4 PCIe 2.0 ports, two of them 16x. This card works great in slot # 2, which is a single wide slot. Slot 1 in the Mac is double wide, but that's occupied by an AMD Radeon RX 580.Which means that this card blocks slot 3, only leaving one additional slow available. Also, the NVMe blades get very hot and after a bit, I noticed "artifacts" on the screen that weren't there before and didn't re-appear after the card was removed.Black Magic's SSD benchmark shows this card with 2 Samsung 2TB (4TB in total) achieve write speeds of up to 2450 MB/sec and read speeds of up to 2895 MB/sec, which is great for an old machine with PCIe 2.0. The card is, however, designed for PCIe 3.0 where it should be twice as fast and maybe not have the artifacts on the screen either.In real-life performance tests, the internal SATA-2 drives that have direct slots on the Mac's motherboard worked better and produced a more linear performance. I mostly use those drives for Virtual machines and where a VM would boot up in 20 seconds on the SATA-2 drives (in a 3-drive RAID0 configuration) it would boot up anywhere between 60 and 180 seconds on this controller. I do not blame the controller for this issue, it might very well be the older PCIe back plane combined with insufficient power. Unfortunately, I had to return the card and the blades.

All of my drives are B-Key sata m.2 drives. I have purchased two of these. One is filled with 5 500GB drives. The second card is populated with 5 1TB drives. Firstly, of no fault of the cards, I ran out of PCI;E lanes on my intel server. Thus, consistent connection issues ensued.I upgraded to an AMD EPYC based platform. Now all drives consistently show up and are stable.PROBLEM:When stress testing all of the 1TB SATA M.2's all at once, one or two will be full speed and the other three will be under 50MB/s. Temperatures of the drives stay nominal.WORKAROUND:Under normal operation in my server the 5 500GB drives are operating flawlessly in the array they are apart of. I have not stress tested the 500GB drives but they are functioning well.FINAL THOUGHT:I am moderately disappointed but not completely butt-hurt. Full bore full-bandwidth not being possible is not ideal but, in the grand scheme of things, I guess a stable connection to that many drives at once is ok.