Most of the times i start my pc and it freezes after a minute or two ..
after that i cant do anything but sometimes i get a screen with lower resolution and the lowest color quality or the pc starts beeping until i restart it manually..
everyday i have to restart it about 2-4 times until it stops freezing and i can use it the whole day after that..
i tried everything and i guess it must be a hardware problem..
Firstly, I would make sure your RAM is in the slot all the way. Secondly, you may want to download and run memtest to make sure that your memory is fine.