1GB [2x512MB] DDR-333 (PC2700) RAM Memory Upgrade Kit for the Sony VAIO PCV PCV-RS420 512MB DDR-333 PC2700 Non-ECC Unbuffered 184 Pin 2.5V CL=2.5 Memory 32X8 When you purchase RAM from 4AllDeals, it comes with a lifetime warranty, as well as lifetime telephone technical support from our US-based technicians. PLEASE NOTE* If you do not purchase this module from 4AllDeals direct, you do not get the lifetime warranty or tech support offered in this ad. Put your trust in a company that has been in business for 12 years, not some fly by night seller you won't be able to get ahold of! 100% Guaranteed Compatible for the computer listed in the title of this ad