he card is specially designed to allow power output from the ninth pin of the connector to enable power up
of the connected devices without power adapter. The card allow user to set each individual port with 5v,12v or RI (No Power)

User can also choose to draw the needed power from the external system power supply.

For Acer Netbook Aspire One & ASUS  Eee PC

PCI-e one chip solution(OXFORD OXPCIe954 chip)

It's real COM Port in your computer, not USB to COM port
  high compatible with serial type device.

Mini PCIe 4 Serial Card in ASUS Eee PC 904HD Mini PCI Express slot

Mini PCIe 4 Serial  in ASUS Eee PC Windows XP Device Manager

The adapter card is based on a oxford single chip design, that allows you to harness the full capability of Mini PCI Express (PCIe) - providing optimum reliability and speed, and reducing the load applied to the CPU by as much as 48% over conventional serial cards.

FEATURES

* Fully compliant with PCI Express Base Specification 1.1
*  Provides four DB9 RS232 ports
* High speed 16C950 compatible UART controller on-board
* Supports serial transmission rate up to 460Kbps
* On-chip hardware auto flow control to guarantee no data loss
* Built-in 128K byte DMA software FIFO
* No IRQ resource required
* Easy Plug and Play Installation
* Works with various types of RS232 serial devices including modems,
  PDAs, label printers, bar code scanners, digital cameras, and more
* Supports  Windows® 2000, XP, Server 2003 ,Vista ,Win7 and Linux
System Requirements:

* Windows® 2000, XP, Server 2003 ,Vista,Win7 and Linux

 * Mini PCI ExpressCard-enabled system with an available Mini PCIe PCI Express Card slot

Accessories:

1 x Manual, 1 x Driver CD, 4 x 9pin serial cable