If it's a third party Amazon seller, like the marketplace sellers, then it is no more trustworthy than from an Ebay seller. If you are going to buy a CPU, buy one that comes with a legitimate warranty from a legitimate retailer. Otherwise, if you get dinged with a bad deal you have nobody but yourself to blame and what you tried to do in an effort to save money can, and OFTEN does, result in it actually costing you significantly MORE than if you'd just gone the straight and narrow route.