Summary: Says it supports 2.4.x or higher but that isn't the case if you are using RHEL5. Contacted techsupport and to there credit they answered super quick but it took a long time to say yea it should work, but then it was well we only support what's in the README and we don't have much info for Linux. I'll go with Intel and not have the problems and get a better card.
Summary: I purchased one of these for my file/game server running on windows XP x64 about two months ago since the motherboard only supported 10/100 speeds and I finally upgraded to gigabit router (D-link DIR-655) and wanted to take full advantage of the throughput it had to offer across my LAN (especially with all of the file transfers and media streaming I tend to do across my LAN).
Summary: don't purchase... vista drivers are not available. the d-link web site indicates that they are coming soon. when i emailed asking when the drivers would be available they responded... Unfortunately we do not have an ETA as to the release of Vista drivers for this unit. Please check the support site often for updates.
Summary: I had one open slot between my SLI video cards for a PCI-Express card and this card works great there. It was easy to install, hooked up to the internet right off, and keeps me in the game. It was a very good card at a very good value (especially if you looked at prices elsewhere).