I ordered 2 memories of this type including 1 defective from the start (this can happen on any material). So I contacted the customer service (in English) Corsair made me drove around for 3 weeks. A bout of patience, I contacted Amazon customer service made me a standard exchange ... thank you for their professionalism. I am a reseller / installer and computer Corsair well I boycott and invites you to go in brands like Kingston.