I have numerous networked devices, some wired, some wireless.
i recently switched cable companies and before i did this, i had no problems at all.
after switching (and i use the same modem), dns is not detected.
all my computers think my router is the dns server and for some reason the tivos still have a dns listing.
More info: I ran ethernet to the entire apartment after this started and i think there may be a problem with the cable network. I can set my router into gateway mode and that fixed the dns for the wired devices but not the wireless (confused) but more confusing, everything is still getting ip addresses assigned when i do this.
So here's my network map as i have it currently set:
rca cable modem
asus rt-n10 router (normal dhcp settings)
4 win7 boxes, 2 tivos all wired
2 win7 laptops wireless
one wii
i've had to manually assign dns settings on everything when it's in router mode, and everything except the tivos when it's in access point mode, and i haven't had to mess with ip addresses in either mode.

Could it be a new problem with my router? I can't imagine where the dhcp server is i'm getting ip addresses from, either. The cable company claims they don't have one.