[Kheldar]

can you go back a version? did you have this problem before your upgraded?

since your router is supported by dd-wrt I'd go for that - it'll give you a lot more features

http://www.dd-wrt.com/wiki/index.php/Supported_Devices

installation instructions
http://www.dd-wrt.com/wiki/index.php...RT54G/GL/GS/GX

other things you can try

use the ping command to work out if network is failing and where

eg ping 192.168.0.1 -t
ping ipaddressoftarget -t (keeps pinging - cntrl-c to stop)

so you'd want to ping your router & other pc's on network if any and then you could ping a website

ipconfig /all

prints out network settings, do this and post results to give us more info

nslookup www.google.com - will translate webaddresses into ipaddresses - it could be a dns failure

you could also try

netsh winsock reset - this will require a reboot


all of these commands need to be used in the command prompt (start, run, cmd)