Neweggs Boo Boo. AMD dropped the warranty for OEMs along time ago. None. They use to have 1 year. But now the only warranty for a OEM processor is from who ever you bought it from. usually 30 to 90 days.
Intel has none on OEM either.
I think I got extremely lucky with mine. Before I bought it from OcUK I emailed them to confirm the warranty of it. They sent me an email stating that the OEM processor has the same warranty as retail, however it doesn't come with the box or fan, you just get the chip, so I have the same warranty as a retail ship. If it dies with in 3 years, I have them over a barrel because of that 1 email where they stated to me that it has full normal warranty under them

The reasoning behind them dropping the warranty, I don't know.
The only thing I can think of is that most OEM processors will be going into prebuilt systems, as they are cheaper to get because of lack of HSF and packaging, along with a POS heatsink. Because of that, most system builders cut corners, so the systems are put together with crap components and cooling, so the chances of a problem occuring are much higher.
However, how true that is, I am not sure, as most warranties are void if the component is damaged due to another component failure, and you lose warranty if it isn't an AMD recomended heatsink too. I am clutching at straws tbh, the reasoning behind not offering the same warranty, other than to save some money, isn't obvious to me