This forum does not have a classifieds section, you will have to find some local US forum that does. I am based in the UK so not familiar with the US forums.
Please check that each of the sticks is working in your new system. Test one stick at a time. I guess you have done this but hey no harm in stating again just in case.
Once you are sure each stick is working then test each memory slot with a known working stick of memory.
Will check back in a few hours.
To help us help you - please provide as much information about your system and the problem as possible.