Wireless network connection

Googled this up and can't find anything, so I come to /tech support/
On Vista. Sometimes, not always or even often, when I leave my computer idle for a few hours and come back I find the network animation thing in the system tray look as if it can't find any wireless networks. So I go look at the network connections thing and it says the wireless network connection is disabled. And no matter how many times I try to enable it again it stays disabled until I reboot, then it works normally again.
It used to do this about year ago but then stopped for ages, I just upgraded to Vista Ultimate (from Home Premium) and it just did it again last night.
Any idea what's going on?
And the weird thing is, when it does this the ethernet cable will work fine, so it's just fucking up the wireless.

>>1

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　　　　　　　　　 （　´∀｀）　＜　GO TO THE CONTROL PANEL ,SYSTEM TRAY , THEN TO THE TAB WITH YOUR THINGS THE ONE THAT SHOWS WICH THINGS ARE WORKING THEN FIND THE UNIVERSAL BUS CONTROLLER AND PROPERTIES THE ENERGY ADMINISTRATION FOR UNIVERSAL BUS CONTROLLER =\= FROM THE POWER OPTIONS BTW THEN UNCHECK THE ALLOW THIS EQUIPMET TO TURN OFF THE DEVICES TO SAVE ENERGY also 2WIRE 2701HG DISSCONECTS NO MATTER WHAT HAVES A HARDWARE FAILURE ISSUE AND BAD DESIGN
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