I ran into the exact same problem a couple months ago, but mine was effecting both the wireless and wired side. My desktop would show "cable disconnected" every minute or so, and then reconnect. One of my laptops would say connected but internet access wouldn't work until I repaired the connection. After chasing my tail for about a week updating drivers, swapping cables and firmware updates, I ended up replacing the router. Everything has been rock solid for months.
I'm not saying this is your problem, but it's what solved my issues.
Edited by Spyderturbo007, 12 March 2010 - 09:10 AM.