Not enough physical memory is available to power on this virtual machine with its configured settings

My Laptop Configurations:

• Intel Core i5 3210M 2.5 GHz
• 6 GB DDR3
• 750 GB 5400 rpm Hard Drive
• 14-Inch Screen
• Windows 8

VMware Player:

VMware Player 5:

On VM,my configuration is

RHEL 4,HDD:20 GB, RAM:512 & 1024 MB(tried both config)

Error Facing:

Not enough physical memory is available to power on this virtual machine with its configured settings.

Please help me.i will share the VM log very soon..