Its the RAM. This message will most commonly appear on that reason alone. You need to try swapping the sticks, or just use one stick and use process of elimination. Find out if they are all bad.
If you have a 2nd computer or can somehow burn a disc, try this to test the memory as well:
www.memtest86.com
Needless to say, it is a hardware problem will need replacement. Check first to make sure all of the modules are installed securely and clicked in securely. Try switching them around or finding out if only one module is bad by using 1 slot to test each one.