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Serial port cards are essential for connecting legacy devices or specialized equipment to modern computers. Ensuring compatibility and reliable performance is key, especially in industrial, scientific, or networking environments where these connections are critical. Choosing the right card can prevent connectivity issues and ensure seamless operation of your peripherals.
MEETS INDUSTRY STANDARDS: The 2-port PCI express serial card is compliant with PCI Express 1.0a specification, and it's compatible with 1x, 2x, 4x, 8x and 16x PCI Express slots.
MAXIMUM COMPATIBILITY: The dual port DB9 to PCIe adapter is ideal for system upgrades in a wide range of applications including manufacturing equipment, POS equipment, and security devices.
HIGH-PERFORMANCE COMMUNICATION: The low-profile serial card delivers high-performance serial communication, with support for data transfer rates of up to 460Kbps.
SIMPLE INSTALLATION: The PCI dual serial adapter features IRQ sharing and supports plug-and-play connection. It has a standard-profile bracket installed, and an optional low-profile bracket.
1. PCIE-SE2 allow users add 2X RS232 BD9 serial Ports on desktop PCs or industrial devices by motherboard PCI Express slot.
2. Seamless connect to serial DB9 ports device such as POS system, industrial testing and control device, security system, logistic management equipment, scanners and printers.
3. Need to install driver on Windows XP, Vista, 7, 8.x, 10, 11 (32/64bit) systems. Linux kernel 2.6.x, 3.x, 4.x, 5.x need to refer compile source code from the driver CD.
4. Selected by ASIX AX99100 solution supports on chip 256-byte depth FIFO in transmit. Works on Intel, AMD, ARM hardware platform.
5. The full-size bracket on this expansion card will works on standard size PCs. The 2X low profile bracket for slim PCs. Based on PCIE X1 interface, will works on X1, X4, X8, X16 slot.
6. ATTENTION: 1. Must make sure users PCs have empty PCIE slot.2. Slim PC users need change to low profile bracket by hand. 3.Please install correct driver from Mini-CD for desktop PCs.
1 PORT SERIAL CARD: Serial controller card w/ 16950 UART based on ASIX AX99100, allows 1x DB9 port w/bi-directional RS232 speeds up to 921.6Kbps per port, available 256 byte FIFO buffer & 9th data bit; Upgraded version of our popular card PEX1S952LP
OPTIONAL CONFIGURABLE POWER: PCI Express RS232 serial adapter card provides choice of 12v, 5v, or none through pin 9 w/up to 2A total
STANDARD PROFILE & LOW PROFILE BRACKET: PCIe serial card comes w/ a low profile bracket pre-installed & 1x full profile bracket is incl for versatile install; Supports Windows & Linux
VERSATILE APPLICATIONS: For low/standard profile desktop/servers w/ uses in point of sale terminals, PLCs, control/automation in factories, scientific sensors, medical equipment, scanner, oscilloscope
Expansion Interface: Easily add 2 RS232 DB9 serial ports to desktop PCs or industrial devices via the motherboard's PCI Express slot, meeting a variety of device connection needs
Wide Compatibility: Seamlessly connect to DB9 serial devices such as POS systems, industrial testing and control equipment, security systems, logistics management devices, scanners, and printers, suitable for various application scenarios
Multi-Platform Support: Driver compatible with Windows XP, Vista, 7, 8.x, 10, 11 (32/64-bit) and Linux kernels 2.6.x, 3.x, 4.x, 5.x, ensuring smooth installation and use across different systems
Efficient Data Transmission: Utilizes the ASIX AX99100 solution, supporting 256-byte deep FIFO transmission, compatible with Intel, AMD, and ARM hardware platforms, providing stable serial data transmission performance
Flexible Installation: Comes with a standard full-size bracket for standard PCs, and includes 2 low-profile brackets for perfect compatibility with slim PCs. Based on the PCIe X1 interface, compatible with X1, X4, X8, and X16 slots
Important: Ensure your PC has an available PCIe slot, switch to the low-profile bracket for slim PCs, and install the correct driver from the Mini-CD for desktop use
Compliant with ExpressCard/34mm Standard; Compatible to 1-Lane (x1) PCI-Express Throughput.
Operating System: Windows 32bit 2000/XP/2003 Server/Vista and 64bit XP/2003 Server/Vista/WIN7/WIN8/WIN10/WIN11/Linux. (If there was any problem with PCIE 2 port serial expansion card, pls feel free to contact us, we will provide a solution within 24hrs.)
Dual Serial Ports: Provides two independent RS232 serial ports, enabling connections with multiple serial DB9 port (RS232 communication) devices, significantly expanding your system's connectivity.
Wide Compatibility: Requires driver installation for Windows XP, Vista, 7, 8.x, 10, 11 (32/64-bit) systems. For Linux kernels 2.6.x, 3.x, 4.x, 5.x, source code on the driver CD can be compiled.
Advanced Chip Solution: Utilizes the ASIX AX99100 solution supporting 256-byte depth FIFO transfer on-chip, suitable for Intel, AMD, and ARM hardware platforms.
Versatile Bracket Design: Comes with a full-size bracket for standard PCs and a low-profile bracket for 2U computers. Compatible with PCIe x1 slots and also fits x4, x8, x16 slots.
Important Notes:Ensure your computer has an available PCIe slot,for 2U computers, manually replace with the low-profile bracket,for desktop computers, install the correct driver from the Mini-CD.
2 PORT SERIAL CARD: Serial controller card w/16950 UART based on ASIX AX99100, allows 2x DB9 ports w/bi-directional RS232 speeds up to 921.6Kbps per port, available 256 byte FIFO buffer & 9th data bit; Upgraded version of our popular card PEX2S952LP
OPTIONAL CONFIGURABLE POWER: PCI Express RS232 serial adapter card provides choice of 12v, 5v, or none through pin 9 w/up to 2A total; Each of the 2 ports are individually configurable
STANDARD PROFILE & LOW PROFILE BRACKET: PCIe multiport serial card comes w/ low profile bracket preinstalled & a full profile bracket is incl for versatile install; supports Windows XP and up & Linux
VERSATILE APPLICATIONS: For standard/low profile desktop/servers w/ uses in point of sale terminals, PLCs, control/automation in factories, scientific sensors, medical equipment, scanner, oscilloscope
Expansion Interface: Easily add 2 RS232 DB9 serial ports to desktop PCs or industrial devices via the motherboard's PCI Express slot, meeting a variety of device connection needs
Wide Compatibility: Seamlessly connect to DB9 serial devices such as POS systems, industrial testing and control equipment, security systems, logistics management devices, scanners, and printers, suitable for various application scenarios
Multi-Platform Support: Driver compatible with Windows XP, Vista, 7, 8.x, 10, 11 (32/64-bit) and Linux kernels 2.6.x, 3.x, 4.x, 5.x, ensuring smooth installation and use across different systems
Efficient Data Transmission: Utilizes the ASIX AX99100 solution, supporting 256-byte deep FIFO transmission, compatible with Intel, AMD, and ARM hardware platforms, providing stable serial data transmission performance
Flexible Installation: Comes with a standard full-size bracket for standard PCs, and includes 2 low-profile brackets for perfect compatibility with slim PCs. Based on the PCIe X1 interface, compatible with X1, X4, X8, and X16 slots
Important: Ensure your PC has an available PCIe slot, switch to the low-profile bracket for slim PCs, and install the correct driver from the Mini-CD for desktop use
Last update on 2026-09-01 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Serial Port Cards
Understanding Serial Port Types
Serial port cards primarily offer RS-232 interfaces, but variations exist. RS-422 and RS-485 offer longer distances and multi-drop capabilities, often used in industrial automation and networking. Consider the specific protocol your devices require. Most cards utilize PCI, PCIe, or USB interfaces to connect to your computer. PCIe is the modern standard for internal cards, offering higher bandwidth than older PCI slots.
Key Features to Consider
Number of Ports: Determine how many serial devices you need to connect simultaneously. Cards are available with one, two, four, or even more ports.
Connector Type: Most common is DB9 (9-pin male or female), but some devices may use DB25 or other connectors. Ensure the card's connector matches your devices.
Chipset: The chipset (e.g., FTDI, ASIX, CH340) influences driver support, stability, and performance. Look for well-regarded chipsets known for reliability.
Power Requirements: Some serial devices require power from the serial port itself (often referred to as "phantom power"). Check if the card offers selectable or adjustable power output if needed.
Operating System Compatibility: Ensure the card has drivers available for your specific operating system, whether it's Windows, macOS, or Linux.
Installation and Driver Considerations
Internal cards (PCIe) require opening your computer case. External USB-to-serial adapters are plug-and-play for most modern systems. Always download the latest drivers from the manufacturer's website to ensure optimal performance and compatibility. Check reviews for common driver issues or installation hurdles.
Use Case Scenarios
These cards are vital for connecting point-of-sale systems, industrial machinery, scientific instruments, GPS receivers, and older networking equipment. For robust, long-distance communication or connecting multiple devices on a single bus, consider RS-485 or RS-422 options. For general-purpose device connections, RS-232 is usually sufficient.
Frequently Asked Questions
What is the difference between RS-232, RS-422, and RS-485?
RS-232 is a single-ended standard for short-distance communication. RS-422 and RS-485 are differential signaling standards that offer better noise immunity, longer cable lengths, and the ability to connect multiple devices on a single bus.
Do I need a DB9 or DB25 connector?
This depends on the serial port connector on your device. DB9 is the most common for modern serial devices, while DB25 is found on older equipment or specific networking gear. Always check your device's specifications.
What is a serial port card chipset?
The chipset is the main integrated circuit on the card that controls its functionality. Popular chipsets like FTDI are known for their reliability and broad driver support across various operating systems.
Can I use a USB-to-serial adapter instead of an internal card?
Yes, USB-to-serial adapters are a convenient alternative, especially for laptops or systems without available internal slots. They are generally easy to install and compatible with most modern operating systems.
What is phantom power on a serial port?
Phantom power is a small amount of voltage supplied through the serial port's pins to power certain devices. Some serial port cards offer selectable power output options to accommodate devices that require it.
How do I know if a card is compatible with my OS?
Check the product specifications or manufacturer's website for a list of supported operating systems. Look for cards that explicitly mention support for your version of Windows, macOS, or Linux.
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