Hi, I'm Jewel with Kingston Technical Support and would like to offer our assistance. We do not actually put serial numbers on the memory or packaging but if the memory was sold as a kit the revision number starting with 99 (looks like 9912345-123.A00LF) should match on them. If it was sold as a 4GB kit of two than each module should be 2GB but if it was sold as an 8GB kit of two each module should be 4GB. As Kingston is a highly recognized name in memory it is possible that you may have recieved counterfeit memory. We are aware of the counterfeit market and work to reduce/eliminate counterfeit products available on the market. As we take these issues very seriously, we ask for your assistance in our attempt to stop traders selling counterfeit Kingston products. We would greatly appreciate it if you could provide us information about the vendor. You can provide this information to our counterfeit team at the following link.
http://legacy.kingston.com/company/counterfeit.asp . We assure you any information you provide to us will be treated with strict confidentiality. Please keep in mind that vendors may buy products in bulk from someone else thinking the items are legitimate, so we do not assume they are the counterfeiter. Finally, we urge you to be pro active where counterfeit products are concerned, and to purchase from one of our authorized vendors.
http://www.kingston.com/wheretobuy/default.asp?id=2