Wlpncp asked the Desktops forum if a PC with a 802.11b/g wireless adapter will work with a 802.11n router.
Yes, it will work. The 802.11n standard is backward compatible.
Updating the card might improve your Internet throughput, but then again, it might not. The old 802.11g tops out at 54Mbps, which is almost certainly faster than your Internet connection (assuming you're living in the USA). But WiFi speed can be effected by distance, physical obstructions, and electronic interference. If these factors slow down your connection sufficiently, the newer standard could speed things up.
You might want to visit http://speedtest.net/ and check your connection's speed. If it's reasonably close to the speed you're paying for (which you will seldom or never receive), upgrading the card won't help. Your Internet connection, not your WiFi, is the bottleneck.
However, if the speed is well below what you're paying for, the distance between your router and your computer--and the walls and other objects between them--could be hurting the WiFi signal and thus slowing performance. Upgrading to 802.11n might help.
And if you're passing large files between computers in your home--in other words, using the network heavily for purposes not related to the Internet--it will help immensely.
Of course, if your desktop is in the same room as the router, there's no need to use WiFi, at all. Ethernet makes the better choice.
Read the original forum discussion.
Contributing Editor Lincoln Spector writes about technology and cinema. Email your tech questions to him at firstname.lastname@example.org, or post them to a community of helpful folks on the PCW Answer Line forum.