First Find your computer's memory usage?
- win + r -> msinfo32 -> ok ->
This shows excact amount of memory used by RAM in your PC which is 2gb or 3.12gb maximum.>>Here is the simple step will solve you the problem
Step 1: . Now press "Windows Logo Key + R" to open Run Command
Step 2: Type "msconfig" and press enter
Step3 : Go to "Boot" tab in it
Step 4: Now press "Advanced options"
Step 5: Untick "Maximum memory" option
Step 6: Click "OK" and Restart Your Computer
