Product ID: PEX4S553B
The PEX4S553B 4-Port PCI Express Serial Card (with breakout cable) lets you add 4 RS232 serial ports using a single PCIe expansion slot, with an included 1-to-4 cable enabling you to add 4 serial ports to a single low profile slot.
The serial card features a native single-chip design that provides optimum reliability and speed, reducing the CPU load by up to 48% over conventional bridge-chip serial cards - a cost-effective solution for connecting legacy serial devices to PCIe-enabled computers.
The multi-port serial adapter includes both full profile and low profile/half-height brackets for compatibility with standard and small form factor computers, and is compatible with a broad range of operating systems, including Windows®, Linux, and MAC OS.
This product is a replacement for our PEX4S552B card.
Backed by a StarTech.com lifetime warranty and free lifetime technical support.
|Connector(s)||1 - Connector Type(s)||PCI Express x1|
|4 - External Ports||DB-9 (9 pin, D-Sub)|
|Environmental||Operating Temperature||0°C to 70°C (32°F to 158°F)|
|Storage Temperature||-40°C to 85°C (-40°F to 185°F)|
|Bus Type||PCI Express|
|Card Type||Low Profile (SP bracket incl.)|
|Port Style||Dongle (Included)|
|Chipset ID||ASIX Moschip MCS9904CV-AA|
|Packaging Information||Package Height||41 mm [1,6 in]|
|Package Length||14,5 cm [5,7 in]|
|Shipping (Package) Weight||343 g [12,1 oz]|
|Package Width||20,8 cm [8,2 in]|
|Max Baud Rate||230.4 Kbps|
|Data Bits||5, 6, 7, 8|
|Parity||Even, Odd, None, Space and Mark|
|Physical Characteristics||Weight of Product||239 g [8,4 oz]|
|Product Length||80,5 mm [3,2 in]|
|Product Width||12 mm [0,5 in]|
|Product Height||6,8 cm [2,7 in]|
|Software||OS Compatibility||Windows® DOS, 95, 98SE, 2000, CE 5.0/6.0, Embedded System 2009, POS Ready 2009, XP Embedded, XP, Vista, 7, 8, 8.1, 10
Windows Server® 2003, 2008 R2, 2012, 2012 R2, 2016, 2019
Mac OS® 10.4 to 10.10
Linux 3.5.x to 4.11.x LTS Versions Only
|Microsoft WHQL Certified||Yes|
|What's in the Box||1 - Included in Package||4 Port PCI-Express Serial Card|
|Full profile bracket|
Prior to installing this device, ensure that your operating system is up to date (for example, you have installed the most recent service pack).
To install the driver:
Note: Windows will typically save the files to the Downloads folder that is associated with your user account (for example, C:\Users\your_name\Downloads).
Note: If the Run as Administrator option is not available, you might be attempting to run the installer from within the zipped file. Extract the files using the instructions in Step 2.
To install the driver:
Note: Windows will typically save the files to the Downloads folder that is associated with your user account (for example, C:\Documents and Settings\your_name\My Documents\Downloads).
Before you install the device, make sure that your operating system is current (for example, the most recent service pack is installed).
Note: Windows usually saves the files to the Downloads folder that is associated with your user account (for example, C:\Users\your_name\Downloads).
Note: The Select your device’s type from the list below screen does not appear on all systems. If you do not see this screen, skip this step.
Note: To view your system type, press Windows key + R, type control /name microsoft.system, and press Enter.
Note: Windows usually saves the files to the Downloads folder that is associated with your user account (for example, C:\Documents and Settings\your_name\My Documents\Downloads).
Note: The Hardware Type screen does not appear on all systems. If you do not see this screen, skip this step.
Older applications that use serial communication often use legacy hardware addresses that do not work with PCI, PCIe, or USB to Serial products. We recommend contacting the software provider/support team to check if this is the case.
When you troubleshoot issues with a serial device, there are some quick tests that you can complete to rule out potential problems. You can test to make sure that the following components are working correctly and are not the source of the issue:
To test your setup components, try the following:
Use the serial cable, serial port, and serial device in another setup to see if the problem is with the components or the setup.
Use a different serial cable, serial port, and serial device in your setup to see if the problem persists. Ideally, you should test a component that you know works in another setup.
When you test your cables, it is recommended that you do the following:
Test each cable individually.
Use short cables when you are testing.
When you test the serial ports and serial device, it is recommended that you do the following:
Press the Windows key + R, type devmgmt.msc, and press Enter to open Device Manager. Check to see if your device is listed under Ports (COM & LPT).
Make sure that the COM port number is the correct number for the serial device and that the software being used to connect the computer to the serial device uses the correct COM port number.
If the device is listed with an error, follow the instructions on the website to reinstall the drivers.
Note: Some serial devices work only if the COM port number is between a certain range. For example, COM1 to COM4.
Perform a serial loopback test. See this FAQ on how to perform a RS-232 serial loopback test: http://www.startech.com/faq/serial_loopback_test_rs232_windows
To check whether or not an RS-232 serial port is working, perform an RS-232 loopback test by doing the following:
Note: To open a telnet session on the COM port, you need a telnet client like PuTTY or Hyper Terminal. Windows XP comes with Hyper Terminal.
If the loopback test fails, make sure that the serial cable or gender changer that you are using works and that the adapter is in the correct port.
You can check multiple ports at the same time by opening multiple sessions, putting the loopback adapter on one port, and trying to type into each session. When you can see what you are typing, you know that the COM port is working and you can see which port number the physical serial port is. Close the window for the port that you just tested to speed up the testing of the remaining serial ports.
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To confirm that Windows detects your expansion card, complete the following:
Your expansion card is listed according to the name of the chipset. To determine the name of the chipset of your expansion card, navigate to www.StarTech.com and look on the Technical Specifications tab for your product.
To confirm that the Mac OS detects your expansion card, complete the following:
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