How to change channel in Vista

I have a Linksys WRT 54 GL router, I must have changed the channel to
6 now my ASUS laptop running Vista cant't connect but my macbook can.
I have looked for a way to change the channel number in the ASUS but I
can't it was working fine until I made changes to the router. BTW the
router is connected to a win xp desktop. Thanks for any help.