win 7 reboots randomly Kernel-Power

Check your event logs.

Should be some info in there.

Open Event Viewer

Hi everyone!

I recently installed the win7 x64 and over 2 weeks i have this disgusting issue.
As described in this post, there are many behaviors that create this kernel power error. In my case by example, when i access start->Control panel->Uninstall programs my PC reboot instantly! The list of programs is showed, but at end the system is rebooting, logged in event viewer with kernel power.
Others case is when i access a flash site on the web or accessing the configuration of the windows.

I really have no idea about what i have to do to solve it! Follow my configuration, thanks!!

Cpu: Intel Core I7 870 2.93GHz Quad-Core LGA 1156 Box
motherboard: Gigabyte Core i3, I5, I7 (LGA 1156) | GA-H55M-S2HP
Ram: 2x - Patriot 2GB DDR3 1333MHz
Hard Disk: Seagate HDD 500GB SATA2 7200RPM
graphic card: Nvidia GeForce GT 430 1GB DDR3 128-bit
power supply: 3r System 450W | IceAge IA450HP80
Samsung DVD writer

I have a laptop and a new desktop build. when I installed win 7 premium 64 upgrade they started rebooting. Long story short, the problem was Zone Alarm, I uninstalled it and haven't had one reboot since. Hope this helps a lot of you with reboots. It took me long enough to find it. Thanks