Need help

I've reinstalled windows xp sp3 im using 1mb ptcl broadband and shiro modem i've tried using both bridge and pppoe neither of em works.

my problem is that internet explorer stops working in 5-6 minutes after the connection is established but the weird thing is that ikeep getting ping replies and if im downloading something from a website or a torrent it doesnt effect its speed.

ive tried switching dns servers... tried opera ....

when i type nslookup in cmd it says

Default Server: ns1.ptcl.net

Address: 203.99.163.240

and then some ptcl tech guy told me to type yahoo.com in the same window.

Server: ns1.ptcl.net

Address: 203.99.163.240

Non-authoritative answer:

Name: yahoo.com

Addresses: 209.131.36.159, 209.191.93.53 .......

when itold him that he said that this is not possible...

and he told me that you're getting ping replies and youre downloads are working so its not his problem

please help.

ijust reset my modem...

it didnt help.