StarTech
.com 4-port PCI Express RS232 Serial Adapter Card - PCIe RS232 Serial Host Controller Card - PCIe to Serial DB9 - 16950 UART - Low Profile Expansion Card - Windows & Linux , TAA (PEX4S953LP)
*Price sourced from Amazon.com. Last updated 2026-05-23. Price and availability subject to change.
This PCI Express RS232 serial adapter card lets you add four RS232 (DB9) serial ports to your computer through a PCI Express (PCIe) slot. The 4 port PCIe serial card enables you to interact with serial devices, such as card readers, printers, PIN pads, and modems, at speeds of up to 921.6Kbps. Maximum Compatibility With broad OS support, including for Windows and Linux, this PCI E serial card is easy to integrate into mixed environments. The card comes pre-configured with low-profile brackets, and includes optional full-profile brackets, so installation is easy regardless of the case form…
SpecPicks Verdict
SpecPicks classifies StarTech.com 4-port PCI Express RS232 Serial Adapter Card - PCIe… as a niche pick — read recent reviews before buying in the expansion cards category, based on 7 verified Amazon reviews and our ranking model that weights rating × review-volume × price-fit. StarTech's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.
Common buyer scenarios for expansion cards of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.
Pros & Cons
Pros
- ✓ Backed by StarTech's warranty and support channels
- ✓ Ships via Amazon with Prime eligibility and the standard returns policy
Cons
- ✗ Below-average customer rating — read recent reviews before buying
- ✗ Limited review volume so far — fewer data points on long-term reliability
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified
Key Features
- 4 PORT SERIAL CARD: Serial controller card w/16950 UART based on ASIX AX99100, allows 4x DB9 ports w/bi-directional RS232 speeds up to 921.6Kbps per port, available 256 byte FIFO buffer; Upgraded version of our popular card PEX4S952LP
- OPTIONAL CONFIGURABLE POWER: PCIe multiport serial card provides 12v, 5v, or none through pin 9 w/up to 2A total; Each of the 4 ports are individually configurable; DB44 to 4x DB9 breakout cable incl
- STANDARD PROFILE & LOW PROFILE BRACKET: PCI Express RS232 serial adapter card has low profile bracket pre-installed & 1x standard bracket incl for versatile install; Supports Windows XP and up & 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
Full Specifications
| Brand | StarTech.com |
|---|---|
| Style | Low Profile |
| Style Name | Low Profile |
| Unit Count | 1.0 Count |
| Model Number | PEX4S953LP |
| Compatibility | Linux |
| Built-In Media | 4-Port Low Profile Serial Card4-Port DB9 Break-out CableFull Profile BracketQuick-Start Guide |
| Item Type Name | Multiport Serial Adapter |
| Mfr Part Number | PEX4S953LP |
| Operating System | Linux,Windows |
| Compatible Devices | Printers, PIN pads, modems, serial devices |
| Hardware Interface | PCI |
| Warranty Description | Lifetime |
| Item Dimensions L x W x H | 2.5"L x 3"W x 0.7"H |
Ready to buy?
StarTech.com 4-port PCI Express RS232 Serial Adapter Card - PCIe RS232 Serial Host Controller Card - PCIe to Serial DB9 - 16950 UART - Low Profile Expansion Card - Windows & Linux , TAA (PEX4S953LP) is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-05-23. Price and availability subject to change.
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