StarTech.com
StarTech.com 2 Port PCI Low Profile RS232 Serial Adapter Card with 16550 UART
Bottom line: The StarTech.com 2 Port PCI Low Profile RS232 Serial Adapter Card: Two 16550 UART RS-232 ports from one PCI slot, up to 115.2 Kbps each; main trade-off: PCI only, so it will not fit modern PCIe-only motherboards.
As an Amazon Associate, SpecPicks earns from qualifying purchases. Full disclosure →
Pros & Cons
Pros
- ✓ Two 16550 UART RS-232 ports from one PCI slot, up to 115.2 Kbps each
- ✓ Low-profile bracket fits SFF and slim desktop cases
- ✓ IRQ sharing lets both ports coexist with other legacy cards
- ✓ Driver support back to Windows XP, Server 2003, Vista, 7 and Server 2008 R2
Cons
- ✗ PCI only, so it will not fit modern PCIe-only motherboards
- ✗ 115.2 Kbps ceiling, slower than modern high-speed UART cards
- ✗ Only 2 ports, so multi-device serial benches need a second card
- ✗ Low-profile bracket may need swapping for a full-height chassis
Manufacturer description
This 2 Port 16550 Serial Card can be installed in a PCI slot to add two serial ports - a cost-effective solution for connecting any new serial device or old legacy serial device, with data transfer rates of up to 115.2 Kbps. The serial card features a low profile bracket, suitable for installation in low profile/small form factor computer cases.Perfect for connecting serial modems, POS devices, PDAs, digital cameras, printers, ISDN terminal adapters and more, to your system, the adapter card supports IRQ sharing and operates flawlessly with Windows 7, Server 2008 R2, Vista, XP, Server 2003…
SpecPicks Verdict
SpecPicks scored StarTech.com 2 Port PCI Low Profile 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
- Add 2 high-speed RS-232 serial ports to your low profile/small form factor computer with a PCI expansion slot
- RS232 Card
- PCI Serial Card
- PCI RS232
- Low Profile PCI Serial Adapter
Full Specifications
| Brand | StarTech.com |
|---|---|
| Style | Classic |
| Style Name | Classic |
| Unit Count | 2 Count |
| Model Number | PCI2S550_LP |
| Mfr Part Number | PCI2S550_LP |
| Compatible Devices | Personal Computer, Printer |
| Hardware Interface | PCI |
| Warranty Description | Lifetime warranty |
| Full listing title | StarTech.com 2 Port PCI Low Profile RS232 Serial Adapter Card with 16550 UART - Serial Adapter - PCI - RS-232 x 2 - PCI2S550_LP |
Ready to buy?
StarTech.com 2 Port PCI Low Profile RS232 Serial Adapter Card with 16550 UART - Serial Adapter - PCI - RS-232 x 2 - PCI2S550_LP is vintage hardware; the used and vintage market on eBay carries most of the live inventory. Prices and condition vary by seller and move in real time, so we link the live listing rather than quote a cached price. It also has an Amazon listing — check it for current price and availability. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
Related Expansion Cards
More guides & deep dives from the SpecPicks archive
Browse all articles & guides →- How to Build a Windows 98 Retro PC in 2026
- Best Retro Handhelds in 2026 — From $35 to $500
- RTX 4070 Super vs RX 7800 XT — Which to Buy in 2026
- Best Budget Gaming PC Build 2026 — ~$1,000 ($800 on Sale)
- Best 1440p Gaming GPUs in 2026
- Emulation Hardware in 2026: FPGA, Software, and Cart-Reader Ecosystems
- The Complete Voodoo5 5500 AGP Driver Guide (2026 Edition)
More reviews from the SpecPicks archive
Browse all reviews →- FIDECO vs Unitek: Best IDE-to-USB Adapter for Retro Drive Imaging
- Handheld Gaming PC Near Me: Where to Buy in 2025
- Meta Is 'Token Managing' Now: Cut Local-LLM Cost on a Single RTX 3060
- Build a 2001 GeForce 3 Windows 98 Gaming PC in 2026: Parts and Setup
- Best Gaming PC Build 2026: 4K Ray Tracing Guide
- Best Mouse and Mousepad for FPS in 2026: G502 Hero + SteelSeries QcK
- AMD Ryzen AI Max+ 395 vs Mac Studio M4 Max for Local LLM Inference
- Gemma 4 Stealth Update Fixes Tool Calling: What Changes Locally
- Raspberry Pi Projects for College Students: 2026 Guide
- AI Technologies We'll Realistically See in Our Lifetimes
- Modern PC Builds vs Period-Correct Retro Rigs: A 2026 Comparison
- Llama.cpp Console Released: What Changes for Local LLM Operators on a 12GB GPU
- Best Mini PC for Local LLM Inference in 2026: Ryzen vs Apple vs Intel
- Best Retro Gaming Storage Adapters for Win98 and DOS PCs in 2026
- Troubleshooting Voodoo 5 5500 PCI Driver Hangs on Windows 98 SE: Field Guide
- A 2007 Samsung UMPC Becomes a Wii U Gamepad
- PFlash on a Single RTX 3090: 10× Prefill Speedup at 128K Context vs llama.cpp
- Voodoo5 5500 PCI Boots on a Modern Z77 Board: Retro-on-Modern Just Got Easier
- Logitech G29 vs HORI Force Feedback: Which Sim Wheel for Beginners?
- Intel Core Ultra 7 270K Plus: Dual-Channel Memory Scaling Tested
- LM Studio vs Jan.ai vs Ollama on an RTX 3060 12GB: Which Local Runner Wins?
- Sound BlasterX G6 on a Retro Windows XP Rig: USB Audio for Period-Correct Builds
- Best 12GB GPU for Local LLMs in 2026
- What Happened to the LLM Training Data Shortage?
Earliest SpecPicks reviews
Browse full archive →- Best GPU for Llama 3.1 8B (2026)
- Best GPU for Qwen 3 14B (2026)
- Best GPU for Qwen 3 32B (2026)
- Best GPU for Llama 3.1 70B (2026)
- Best GPU for DeepSeek-R1 32B (2026)
- Best GPU for Llama 3.1 405B (2026)
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 5090
- How to run Qwen 3 14B on NVIDIA GeForce RTX 5090
- How to run Qwen 3 32B on NVIDIA GeForce RTX 5090
- How to run Llama 3.1 70B on NVIDIA GeForce RTX 5090
- How to run DeepSeek-R1 32B on NVIDIA GeForce RTX 5090
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 4090