|Your computer has nothing to do with your ping. Your network or Internet Service Provider is what is responsible for your ping. Do the following and post the results...|
Goto the Command Prompt and type...
tracert yahoo.com > pingresult.txt
then open the pingresult.txt and paste the results. With this we can determine which node in your network is slowing you down.
P.S. can you do this too...
ping -n 10 yahoo.com >> pingresult.txt
so that we can see if you are getting any packet loss.
One last thing that will decrease you ping result is a virus like spy ware which is robbing some of your band width to transmit information. Can you do a netstat so we can see if there are apps that have ports open on your computer that should not...
netstat -b > portsopen.txt
If you are running Vista or 7 then you will need to run the command prompt as administrator to run this command.