You have windows 32-Bit to use over 4GB of ram you need 64-Bit
No i have 64 bit version and the problem was my fan connected to the heat sink was pushing down on and it got it stuck so i took it out and put it back and fixed it
Is it a third party cooler, if so may have it too tight in a corner or side which can throw off the MC (memory controller), try loosening the cooler and then snug it down screw tight