Vista - Weird issue with Internet Network ?

i'm having a weird issue with my internet network(never had it before).

i just built a new desktop and install vista X64 ultimate on it (everything works fine), my wifes laptop has vista home premium X86.

for some reason when i reboot the desktop it kills my internet connection for both computers! it does come back after a short while maybe 2 -5 mins later after vista finishes booting up.

they are both set as home network computers. never had this issue before when my old desktop had XP Pro on it.

any ideas to try would be greatly helpful.

i have already unchecked IPv6 on both computer as i thought that was the issue but it still does it

oh yeah almost forgot when it does this i can still talk to both computers thru the network I.E. i can look at my desktop from her laptop and vise versa.

im guessing your using a LAN connection if that is the case
look at the router\modem when you reboot does the power go out there too

laptop is wireless desktop is wired and no the router stays powered

oh yeah just remembered also the network icon in the notification area stays the same and says i have local and internet with the two screens and the earth. but i cannot get on the internet at all