StarTech.com
StarTech.com StarTech 1-Port PCI Express RS232 Serial Adapter Card
Bottom line: The StarTech.com StarTech 1-Port PCI Express RS232 Serial Adapter Card is a specs-and-price decision rather than a crowd-consensus one in the expansion cards category, priced around $49.99 on Amazon as of 2026-10-06. Check the specification table below against one or two close alternatives — on price and spec fit, not on star ratings.
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*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Backed by StarTech.com's warranty and support channels
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, shipping and returns are set by the retailer and may have changed since this page was last updated
Manufacturer description
This RS232 Serial Adapter Card lets you add an RS232 (DB9) serial port to your computer through a PCI Express (PCIe) slot. It enables your system to interact with serial devices, such as card readers, printers, PIN pads, and modems, at speeds of up to 921.4Kbps. Maximum Compatibility With broad OS support, including for Windows and Linux, this PCI Express card is easy to integrate into mixed environments. The card comes pre-configured with a low-profile bracket, and includes an optional full-profile bracket, so installation is easy regardless of the case form factor. Experience Optimal…
SpecPicks Verdict
SpecPicks scored StarTech.com StarTech 1-Port PCI Express RS232 Serial Adapter Card using a rating × review-volume × price-fit model applied to published specs and reviews across the expansion cards category. StarTech.com's expansion cards lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
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 retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- 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
Full Specifications
| Brand | StarTech.com |
|---|---|
| Style | 1 Port |
| Style Name | 1 Port |
| Unit Count | 1.0 Count |
| Model Number | PEX1S953LP |
| Compatibility | Linux |
| Item Type Name | Serial Adapter |
| Mfr Part Number | PEX1S953LP |
| Compatible Devices | [Devices with PCI Express slot and compatible operating system] |
| Hardware Interface | PCI |
| Warranty Description | Lifetime |
| Item Dimensions L x W x H | 3.9"L x 2.6"W x 5.9"H |
| OPTIONAL CONFIGURABLE POWER | PCI Express RS232 serial adapter card provides choice of 12v, 5v, or none through pin 9 w/up to 2A total |
| Global Trade Identification Number | 00065030881159 |
| 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 |
| Full listing title | StarTech 1-Port PCI Express RS232 Serial Adapter Card, TAA (PEX1S953LP) | PCIe RS232 Serial DB9 Host Controller Card, 16950 UART, Low Profile Expansion Card for Windows and Linux |
Ready to buy?
StarTech 1-Port PCI Express RS232 Serial Adapter Card, TAA (PEX1S953LP) | PCIe RS232 Serial DB9 Host Controller Card, 16950 UART, Low Profile Expansion Card for Windows and Linux is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
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