Imac 2.4 ghz 250 hard drive
I just installed 4 g of 800mhz crucial ram and my computer is reading it but after about 1 1/2 min it freezes and half the screen will be blue and t makes this wierd sound does anyone have any idea what this is

And yes it does say on the menu about this mac
2.4 ghz
4 gb ram 800mhz