Because you told us nothing about your system, that's all I can say.
What machine?
What OS?
DSL, cable, fiber?
What browser?
What company?
What, exactly, happens to cause a reboot? Error messages?
I used to use a dial up network, now I have upgraded to high speed internet. For some reason I can not get on the internet. I am using the company modem/ethernet line. The company says I am all hooked up and ready to go but when I click on my internet link it can not display the page and freezes up causing me the need to reboot.
I need help

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GameSpot
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TechRepublic