On my Shuttle PC XPC Sp2 Pro with 3.16 GHz I have Win7 Ultimate 64-bit instaliert.Zu the existing 2GB RAM Corsair not, I gesteckt.Somit the 4GB of Crossair to it are now 6GB Arbeitsspeicher.Das System is schnell.Ausfälle I had been very keine.Bin zufrieden.Zu Amazon: Attention should be ordered here already often and even my son recommended at Amazon the super fast shipping and receiving, as well as to Paketverfolgung.Habe bestellen.Weil I know well looked after me as a customer .Danke Amazon !!! Yours sincerely Werner