Dang, I guess after decades of somehow always buying the proper memory, I got cocky. Back to eBay. Thanks for the info...

Hey Folks, I purchased a 4GB sodimm DDR3, to replace a 2GB stick. However I was not able to boot with the new stick, resulting in lots of beeps pre-post. I tried re-seating the ram, just in case. So for whatever reason it's gotta be incompatible, apparently it came from a Dell. I've posted an image ...