Internet Connection Problems - Is it Hardware or Software problems?

Here's my problem - I can only get full use of my Internet for the first 10 minutes, then I need to reboot my PC to get it back. I get a message telling me that my connection timed out. However, I still have use of my email with exception to those that include web content. It's making me nuts as I no longer know what to do to fix this. I've unloaded and reloaded the tcp/ip protocols, checked all my network connections, tried a different port, removed and reinstalled Firefox (repaired IE), and I still haven't put a dent in the problem. My NIC card is less than two months old. Could use some help here. Thanks.

Go here to download Hijack This. Then scan but do not fix anything yet. Save the scan to a log and then copy and paste the results of scan into a new thread in the Hijack This and Spyware removal forum