I have a HP Pavilion 520c Desktop Computer, and for some reason, It freezes when it GOES on the internet. Then i have to hold the power button for 5 sec's and it will shut down, after restart and trying to online again it does that again, after several times of that, it finally connects to the internet and then im online. But what can be the problem.

I connect to the internet via a telephone line (dial-up) "no charge".
When it freezes nothing works, this includes the mouse, the keyboard and everything. When i try to launch the TASK Manager, it wouldnt even open. After it freezes and i press the Num Lock on the keyboard, the light doesnt turn off. or anything. when i press the CAPS key also the light does not come on. Please I need some suggestions.
Thanks.What web browser are you using?

and

Have you run anti-malware/virus scans?What OS ?
When did this start ?
Any NEW hardware/software recently ?

More info.

patio.  8-)Welcome back Patio.  Patio who?PAY attention! 

Thanx guys !