Internet

Hi, I have a Windows 8 which works fine online, I also have a Windows Vista desktop. I am unable to get online with my desktop, I have called my Time Warner IT support, my first call was 3 hours and no luck, she was very helpful but I needed to contact the next level of help. So 2 days later I called, after 1 1/2 hrs the IT guy said it was my Ethernet cable and card ( he was very short with me, I think he didn't want to help anymore.). I went and spent $ 80, my friend took the entire machine into his work and it worked fine. He gave me a new Ethernet cord and I returned the one I bought as well as Ethernet card, getting back my $ 80 and saving me from taking it in for service. He said to contact my internet service, so I called them, and after 2 hours with yet another tech, I had to call to speak with a level 3 tech. After 2 hours with her we did all troubleshooting and was told I needed to update my driver. I just tried and again, no luck. I keep thinking it may be my modem. When I turn it off then on all lights are on but only the power and Ethernet light stay on. The problem began about a month ago, the night before my power was off for about 30 seconds or so and the next day was when it began. I thought it was my modem and still do. I am So frustrated, I had to take a break in between each call to Time Warner, some times I would wait a few days because I can't figure this out. Can somebody help me, I wish I knew Bill Gates' number. Thanks