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GLOTRENDS specializes in developing high-performance PCIe adapters and riser cables for computer engineers and DIY enthusiasts.
The products mainly include 2 series: PCIe adapters (M.2 SSD Adapter, SATA Card, WiFi/Ethernet Card, USB Card, etc) and PCIe 5.0/4.0/3.0 extension cables.
The goal of GLOTRENDS is to provide quality-assured and cost-effective products to customers worldwide. Customized production is welcome.
M2 Adapter without Bifurcation
M2 Adapter with Bifurcation
PU41
- U.2 PCIe 4.0 X16 Adapter
- 4 x U.2 SSD
U.2 Adapter
SFF-8643 PCIe Adapter
EM6001
- 80Gbps M.2 NVMe SSD Enclosure
- JHL9480 B2 Controller
M.2 NVMe SSD Enclosure
M14
- E1.S to PCIe 5.0 X4 Adapter
- Windows 8/10/11/Linux/macOS
Accessories for M.2 SSD
Model: PA21
PCIe Bifurcation in ASUS BIOS
Enable Hyper M.2 <---> Advanced\Onboard Devices Configuration
PCIe Bifurcation in MSI or others BIOS
Configure PCIe x4+x4 or x4+x4x4+x4
Software RAID for M.2 NVMe SSD
RAID Setup in Window 10/11
- When you locate 2 separate M.2 NVMe SSDs in Windows 10/11 Disk Management
- Right-click the disk volume you want to set up as a soft RAID
- A pop-up window will appear; click the desired option (Spanned/Striped/Mirrored)
Similar Product Comparison
 PA21 |  PA20 |  PA52 |  PA54 |  ST560 |  PA44 |  ST558 | |
|---|---|---|---|---|---|---|---|
Customer Reviews | — | — | — | — | — | — | — |
Price | — | — | — | — | — | — | — |
M.2 Slot | 2 | 2 | 2 | 4 | 4 | 4 | 8 |
PCIE Bus | PCIe 4.0 X8 | PCIe 3.0 X4 | PCIe 5.0 X8 | PCIe 5.0 X16 | PCIe 3.0 X8 | PCIe 4.0 X8 | PCIe 4.0 X16 |
PCIe Bifurcation | No | Yes | No | No | Yes | Yes | Yes |
Software RAID | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Support Mac Pro | No | Yes | No | No | Yes | Yes | Yes |
What does "Bifurcation Required" mean?
The PA21 has no chip that splits PCIe lanes by itself. Your motherboard must split the x8 slot into two x4 links (x4x4) and that option must be enabled in the BIOS/UEFI. If it is not, the system detects only the SSD in the socket marked NVMe-1.
How do I check whether my motherboard qualifies before buying?
Open the motherboard manual, find the PCIe expansion slot section, and look for "PCIe bifurcation", "lane splitting", "x4x4" or "Hyper M.2". Then check the BIOS for the same menu.
What speed will I get with PCIe 3.0 hardware or a PCIe 5.0 SSD?
The card is PCIe 4.0 x8. Full 64Gbps per drive needs a Gen4 CPU, Gen4 slot and Gen4 SSDs. On Gen3 or Gen2 systems the drives run at those generations' speeds. A Gen5 SSD will run at Gen4 x4 speed at best.
What is in the box?
PA21 card, full-height and low-profile bracket, M.2 mounting screws and brass standoffs. The brass standoffs are pre-fitted on the underside of the PCB: move one to the hole that matches your SSD length, seat the drive, then fix it from the back.
Model: PA21
| Interface to PC | PCI-Express 4.0 X8 (128GBbps at max) |
|---|---|
| Interface to SSD | 2 x Key M ( Support 2230/2242/2260/2280/22110 form factor) |
| OS Compatibility | Windows 11/10/8, Linux, macOS; not Windows 7 and Mac Pro |
| PCIe Bifurcation | Not support, so it requires a motherboard that supports PCIe Bifurcation |
| Hardware Platform | Intel and AMD motherboard with PCIe Bifurcation (Note: not support Mac Pro) |
| CPU Requirements | Intel 11th Gen or Ryzen 5000 Series and above |
| RAID Setup | Software RAID setup via Windows Disk Management or Linux mdadm Utility |
| Host Slot | PCIe x8 or x16 electrical slot with bifurcation enabled in BIOS |
| PCIe Compatibility | PCIe 4.0 / 3.0 / 2.0 backward compatible at respective speeds |
| Gen4 Full-Speed Requirement | Gen4 CPU (Intel 11th Gen or newer), Gen4 slot and Gen4 SSD |
| OS Boot | UEFI boot from an SSD on the card, subject to motherboard NVMe boot support; older boards = storage only |
| Installation | Low-profile and Regular-profile bracket |
PCIe Bifurcation in ASUS BIOS
Enable Hyper M.2 <---> Advanced\Onboard Devices Configuration
PCIe Bifurcation in MSI or others BIOS
Configure PCIe x4+x4 or x4+x4x4+x4
Software RAID for M.2 NVMe SSD
RAID Setup in Window 10/11
- When you locate 2 separate M.2 NVMe SSDs in Windows 10/11 Disk Management
- Right-click the disk volume you want to set up as a soft RAID
- A pop-up window will appear; click the desired option (Spanned/Striped/Mirrored)
Similar Product Comparison
PA21 | PA20 | PA52 |  PA54 | ST560 | PA44 | ST558 |
|---|---|---|---|---|---|---|
| Customer Reviews | ||||||
| — | — | — | — | — | — | — |
| Price | ||||||
| — | — | — | — | — | — | — |
| M.2 Slot | ||||||
| 2 | 2 | 2 | 4 | 4 | 4 | 8 |
| PCIE Bus | ||||||
| PCIe 4.0 X8 | PCIe 3.0 X4 | PCIe 5.0 X8 | PCIe 5.0 X16 | PCIe 3.0 X8 | PCIe 4.0 X8 | PCIe 4.0 X16 |
| PCIe Bifurcation | ||||||
| No | Yes | No | No | Yes | Yes | Yes |
| Software RAID | ||||||
| Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Support Mac Pro | ||||||
| No | Yes | No | No | Yes | Yes | Yes |
What does "Bifurcation Required" mean?
The PA21 has no chip that splits PCIe lanes by itself. Your motherboard must split the x8 slot into two x4 links (x4x4) and that option must be enabled in the BIOS/UEFI. If it is not, the system detects only the SSD in the socket marked NVMe-1.
How do I check whether my motherboard qualifies before buying?
Open the motherboard manual, find the PCIe expansion slot section, and look for "PCIe bifurcation", "lane splitting", "x4x4" or "Hyper M.2". Then check the BIOS for the same menu.
What speed will I get with PCIe 3.0 hardware or a PCIe 5.0 SSD?
The card is PCIe 4.0 x8. Full 64Gbps per drive needs a Gen4 CPU, Gen4 slot and Gen4 SSDs. On Gen3 or Gen2 systems the drives run at those generations' speeds. A Gen5 SSD will run at Gen4 x4 speed at best.
What is in the box?
PA21 card, full-height and low-profile bracket, M.2 mounting screws and brass standoffs. The brass standoffs are pre-fitted on the underside of the PCB: move one to the hole that matches your SSD length, seat the drive, then fix it from the back.
GLOTRENDS specializes in developing high-performance PCIe adapters and riser cables for computer engineers and DIY enthusiasts.
The products mainly include 2 series: PCIe adapters (M.2 SSD Adapter, SATA Card, WiFi/Ethernet Card, USB Card, etc) and PCIe 5.0/4.0/3.0 extension cables.
The goal of GLOTRENDS is to provide quality-assured and cost-effective products to customers worldwide. Customized production is welcome.
M2 Adapter without Bifurcation
M2 Adapter with Bifurcation
PU41
- U.2 PCIe 4.0 X16 Adapter
- 4 x U.2 SSD
U.2 Adapter
SFF-8643 PCIe Adapter
EM6001
- 80Gbps M.2 NVMe SSD Enclosure
- JHL9480 B2 Controller
M.2 NVMe SSD Enclosure
M14
- E1.S to PCIe 5.0 X4 Adapter
- Windows 8/10/11/Linux/macOS
Accessories for M.2 SSD
