error code 105 :dns server is not looking up

Hello!
Iam facing occasional net connectivity problems even though the internet connection is available ( which i have verified through ubuntu 11.1).
My system configs are
Mobo :asus p8p67 pro
Operating sytem :Windows 7 home premium 64 bit
Lan Card :Intel(R) 82579v Gigabit network connection.
Modem :Teracom ADSL broadband modem with wire
Memmory : 8GB transcend
Browser : Google crome, mozilla, IE, opera

I am getting the error code 105 ( not always) which says DNS server is not looking up. The connectivity will be restored automatically after some time.
I have tried all available browsers but in vain. But the modem is indicating a connection which i have further verified by testing in ubuntu .
Is it a win 7 centric problem ?( it is not a Lan card problem as it is working in ubuntu, sony internet TV)
Any suggestions ?
Thanks in advance

What are you using for DNS settings?
Tried a public DNS? like 8.8.8.8 and 8.8.4.4 (Google Public DNS)
Have you flushed your DNS cache?
Start > All Programs > Accessories > Command Prompt. Right click on it and 'Run as Administrator'. Type the following : ipconfig /flushdns and hit enter.
Have you tried resetting your modem?

Start > Control Panel > Network Sharing Centre (Small Icons View) > Change Adapter Settings > Right-Click your connection > Properties > Double-Click TCP/IPv4 Properties

DNS settings can be changed here.

Hope this helps,

Harry

Thanks for the replies.
I will try it.

Tried the suggestions. It didn't worked at least for my system.
I uninstalled the corrupted adobe flash player/shock wave player( it used to crash frequently in chrome but i dont know whether it is browser specific.) and since then the problem hasn't occurred(?).
Thanks