Product Type | PCI Express Serial Adapter Card |
Form Factor | Plug-In Card |
Chipset | ASIX AX99100 |
UART | 16950 UART |
FIFO Buffer Size | 256 byte per port |
Bracket Type | Standard profile (low-profile bracket included) |
Power Output Options (Pin 9) | 5V, 12V or none (up to 2A total) |
Max Baud Rate Per Port | 921.6 Kbps |
Ports Included | 4 x DB9 RS-232 (via breakout cable) |
Operating System Support | Windows, Linux |
StarTech 4-Port PCIe RS232 Serial Adapter Card - PEX4S953LP





Key Benefits

Eye-Insights™ by Eye-In Technologies
AI-Powered Summaries from Online Customer Reviews
AI-Powered Summaries from Online Customer Reviews
Eye-Insights™ are generated by proprietary AI that analyzes real online customer reviews to highlight top pros and key product features. While we aim for accuracy, insights are provided “as-is” and individual results may vary.
- Provides robust RS-232 support for legacy device integration via PCI Express
- Offers flexible deployment with both standard and low-profile brackets plus breakout cable
- Ideal for industrial and commercial environments requiring multi-port serial connectivity
Product Overview
4 port PCI Express RS232 serial controller card w/16950 UART/ASIX AX99100 - Bi-directional speeds 921.6Kbps/port / 256 byte FIFO / 9th data bit - Pin 9 pwr out 5v/12v/none w/up to 2A total - Std bracket (low profile incl); Breakout cable - Win/LinuxSpecifications
Product Overview
Wireless Features
Compliance & Origin
TAA Compliant | Yes |
Country of Origin | Taiwan |
Certifications | CE, FCC, RoHS |
Warranty | Lifetime Warranty |
Advanced Security Features
Interfaces
Interface Type | PCI Express 1.0a x1 |
Port Count | 4 |
Connector Type | DB9 (via breakout cable) |
Data Transfer Rate | Up to 921.6 Kbps per port |
Serial Port Standard | RS-232 |
Data Bits | 5, 6, 7, 8, 9 |
Stop Bits | 1, 1.5, 2 |
Parity | None, Odd, Even, Mark, Space |
Flow Control | None, Xon/Xoff, RTS/CTS |
Physical & Environmental
Bracket Height | Standard and Low Profile |
Product Height | 18 mm (0.7 in) |
Product Length | 120 mm (4.7 in) |
Product Width | 90 mm (3.5 in) |
Product Weight | 82 g (2.9 oz) |
Operating Temperature | 0°C to 50°C (32°F to 122°F) |
Storage Temperature | -20°C to 70°C (-4°F to 158°F) |
Humidity (Operating) | 5% - 95% RH (Non-Condensing) |