Engineering samples are the beta versions of integrated circuits that are meant to be used for compatibility qualification or as demonstrators.[1] They are usually loaned to OEM manufacturers prior to the chip's commercial release to allow product development or display. Engineering samples are usually handed out under a non-disclosure agreement or another type of confidentiality agreement.
Some engineering samples, such as Pentium 4 processors were rare and favoured for having unlocked base-clock multipliers. More recently, Core 2 engineering samples have become more common and popular. Asian sellers were selling the Core 2 processors at major profit.
While engineering sample CPUs do occasionally appear on secondhand markets such as eBay, they are generally not authorized for resale and can suffer from unpredictable performance issues, compatibility issues, and lack of warranty support options.[2] This is due to their unfinished nature compared to the retail version of the chip.