|Could be loose RAM modules so check they are located in their slots properly and pushed fully home.|
May also be faulty RAM. You can test the RAM with Memtest86 which runs from a bootable CD: Emachines laptop with Continuous Beep on Start-up
Download the "Pre-built ISO for Windows": http://www.memtest.org/
Download & install "IMGBurn" from here: http://filehippo.com/download_imgburn/
Use "IMGBurn" to create a CD from the ISO file.
Boot your laptop from that CD to test the RAM.