Denial of service attack?

I'm not sure but I seem to be getting a denial of service attack or something. I am getting constant pings from a multitude of different IP addresses. When I run the program "Whats running" I see many IP addresses that are pinging me. This is only happening on one of my 5 systems. I am running XP SP3 but I have one other system running the same OS without any trouble.
If I shut off the process it shuts off but comes right back in about 2 minutes. It totally overloads my CPU and network.

I have tried shutting off ICMP but it just switches to HTTP with the same issue. None of my other systems are receiving this attack. I have changed network boards, reloaded my OS with a backup, tried switching to wireless and I have tightened up my router as tight as I know how.

This is really got me stumped. What could be so fixed on this particular system? I have also run my Superantispyware and it found nothing.

My only defense as of now is to disable the network board.


Help!

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Have you tried changing you IP address and see if the problem persists? If the problem continues or starts after a slight delay, you likely have some malware that's sending a call home to DOS your IP.

 

Thanks. That is the only thing I have not tried since I am running DHCP I am probably getting the same address each time. I have tried most everything else but am beginning to suspect that my system is causing the problem because none of my other 5 computers are seeing it. When I saw this issue when I was working in industry networking it was usually all systems saw it thus shutting them all down.

I will try that...........

 

I thought I would let you know my final resolution. There was none so I just rebuilt the system with XP Pro SP3 like it had before. So far there is no further DoS attacks. I suspected my system was causing it since none of my other computers were affected. It was interesting that a backup I restored to the system did exactly the same thing. Now my experiment will be to restore that same backup and see if the problem comes back.

I ran two different anti-virus software packages and neither of them found anything but cookies.

Thanks for your help.............