You are building a Windows XP or Vista gaming rig to play physical discs of Half-Life 2 or World of Warcraft: Wrath of the Lich King . Modern Wi-Fi cards lack XP drivers. An exclusive 802.11n card with signed XP drivers is the only way to get that rig online wirelessly.
For an "exclusive" card pulled from an old enterprise desktop (e.g., HP or Dell branded Broadcom card), you may need to flash a "retail" firmware to remove whitelist restrictions. 80211n wireless pci express card lan adapter exclusive