This Realtek card suffers from the same incompatibility problems as all the other Realtek 8180 based cards: kernel-specific precompiled binary drivers. You must have a kernel that is from version 2.4.21 and below for it to work, forcing you to lose some features not supported in those kernels, and could possibly break your system. It is better to use the ndiswrapper (ndiswrapper.sourceforge.net), as the setup is muc easier and lets you use the newer 2.6.x kernels. Don't buy it if you have to, go for a Prism-based card instead. For more help look for the 'WPC11 Ver 4!' post in the wireless networking forum.

I've been using this card via ndiswrapper, and so far it works perfectly.
One thing to note: Do NOT use the driver on the included CD-ROM. It does not work, causes random keyboard lock up, and other problems. Instead, go to Realtek's website (see below) and download the Windows 2000 driver (not Windows XP; this one will not work).

The drivers can be found here:
http://www.realtek.com.tw/downloads/downloads1-3.aspx?Keyword=8180