AMD K6-2 Marketing Sample

During the development of most any given processor many chips are produced before it is released for commercial use.  These pre-production chips serve a wide variety of purposes in the design and debugging of the processor to ensure that the final CPU work well, sells well, and is compatible with all the vendors parts (motherboards, cooling solutions, power supplies, etc).  These chips are generally referred to as samples, and there is several types of them.  We’ll use Intel/AMD as the main examples but most all processor companies work in similar ways.

When a processor design is first being developed, the package for it is also often being developed as well, what will the new processors silicon die reside in?  How many pins? How will it dissipate heat?  This type of testing is often handled with Mechanical Samples.  Mechanical Samples are exactly as they sound, they test the mechanical aspects of the processor, the physical fit of it.  THese are often sent to board/socket manufacturers to ensure the processor will fit in sockets/boards, and with the automated equipment used to build systems.  Cooling solution companies may also receive these to test how a heatsink fits on the CPU. Mechanical samples may not contain a die at all, or may be chips that were tested as bad, or simply just untested chips (Intel used a lot of untested Mechanical Samples in their educational kits).

Thermal Sample for the LGA2011 Sandy Bridge Xeon

The next samples typically made are Electrical/Thermal Samples.  These again do not have an actually processor die in them, but electrically do work.  Electrical/Thermal samples are used to test the power draw and heat dissipation of a processor.  They often use a daisy chain transistor design, which serves to draw/dissipate power.  If a processor is expected to dissipate 135W of heat, a Thermal sample can be made to draw/dissipate exactly that.  These can test the the power supplies on motherboards, as well as the heat dissipation abilities of cooling solutions.  Some Thermal Samples have a temperature sensor added directly to the package to help see what temps they achieve.  Electrical Samples and Thermal Samples could also be used as purely Mechanical Samples too, and this is sometimes seen marked on the sample.

The first samples made that actually contain a functioning processor die are Engineering Samples.  Engineering Samples (also known as ES) are the most well known samples.  Overclockers often like to find ES CPUs as they will often allow for easier overclocking due to some not having locked in speed (multiplier locked).  Engineering Sample CPUs themselves come in several types as well.  Usually the first run is known as ES1, these can be thought of as an ‘Alpha’ version.  They are very likely to be buggy, and rarely run at the same speed as a production chip would.  These exist to test the overall processor design, or some subset of it.  Some are made to test just one part of the CPU, for example , the memory controller, or the cache.  Later versions of

Motorola PowerPC 8260 Engineering Sample (note the PPC prefix)

Engineering Samples are often called ‘ES2.’ These processors are getting closer to final production and are a lot less buggy, these would be considered ‘Beta’ Samples.  Most of the time these are quite usable chips, and often are very similar in clock speed/features to a production processor.   Intel denoted these chips with a Q-spec (such as QBGC) rather then production processor having an S-spec (such as SL5G8).  AMD typically uses part numbers starting with ‘1’ for ES1 CPUs and ‘2’ for ES2 CPUs. (such as Opterons 1S160805L4BGC or 2S16….).  Other companies have similar methodologies.  Motorola (Freescale) used the PPC prefix for most ES CPUs and Texas Instruments uses ‘TMP’ (not to be confused with Toshiba who also uses the TMP pre-fix, but for processors in general). Once a company is fairly confident a design is ready for release one final version is made.

These are known as Qualification Samples (QS).  QS processors almost always have a one to one equivalence with a production part, since that is their purpose, to make sure the design is ready for release.  These processors are by far the most widely made chips, as they are shipped by

Alchemy Au1000 MIPS Processor – Qualification Sample

the thousands to vendors, system builders/integrations, and even the media outlets for review.  The hope is that nothing major wrong is found with them, and that any bugs that are found can be dealt with in software or firmware, not requiring an entire silicon fix.  Intel continues to use Q-specs for these as well, leading to some confusion with the previously mentioned ES CPU’s.  AMD usually uses part numbers beginning with ‘Z’ for QS CPU’s and like Intel, does not offer these CPU’s for sale to the general public, they are either given to vendors, or sold exclusively to them for testing.   Motorola uses XC, or XPC for these, and unlike AMD/Intel, mass produces these and sells them, often for years, before they decide that a part/design is truly fully qualified/characterized (in which case the prefixe is changed to MC. or MPC).  Texas Instruments uses the ‘TMX” prefix for their Qual. Samples. and tended to make/sell them like Motorola did with theirs, changing the prefix to TMS for fully qualified production parts.

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Mt. Everest – Tallest on Earth

Mt. Everest is the tallest mountain here on Earth, the pinnacle of climbing challenges.  There is no going higher then Mt. Everest.  At Intel the pseudo-unofficial codename for the absolute fastest speed bin of a particular processor is…Everest.  Everest processors are the fastest an architecture will so reliably.  Sometimes these processors end up an normal products, available for consumers to purchase.  The first good example of this is the Core 2 Extreme QX9775 Yorkfield core (Core Architecture).  They were a quad-core processor running at 3.2GHz, fast but not mind blazingly so.  The Xeon equivalent was the X5492 (Harpertown) 4-core at 3.4GHz.

Xeon X5698 – Westmere – 4.4GHz – Mid 2010

The next well know Everest was a chip based on the Westmere (shrink of Nehalem) architecture.  The Westmere Everest became known as the Xeon X5698, and was available for OEMs only, in fact it was a special order processor made with one particular type of client in mind. These were to be used for High Frequency Stock traders, and other such high speed transactional processing, where the ability to complete trades as fast, and reliability as possible is the entire nature of the business.  This means that single thread performance is far more important then having multiple core, and as such, the X5698 uses a 6-core die with only 2 cores active, but retaining access to the entire 12MB of L3 cache.  Clock speed was fixed at 4.4GHz, the cores did not reduce frequency as processing demands changed, as this would introduce uncertainty in how fast it would complete a given task. Doing task ‘X’ should take a predictable amount of time and not depend on what speed the processor chose to run at.  The next fastest Westmere processor was the X5690, which was a 6-core (all cores enabled) running at 3.46GHz (the same chip essentially as the Core i7 990X).  The X5698 was nearly 1GHz faster.  The X5690 cost around $1800, where as the X5698 cost around $20,000 EACH (based on costs OEMs charged to add a 2nd one so they may have marked it up some).  The impressive thing is that these chips would go faster.  Intel sampled 4.66GHz versions and Supermicro built systems using X5698’s overclocked to 4.8GHz.  All this back in 2011.

4.4GHz Jaketown (Sandy Bridge) Everest Sample 2010-2011

Intel’s next architecture was known as Sandy Bridge.  Sandy Bridge topped at at 3.5GHz (6-cores) for the Core i7 Extreme 3970X and 3.6GHz for the 4-core i7-3820 and similar Xeon E5-1620.  Intel demo’d an air cooled Sandy Bridge running on stage for a presentation at 4.9GHz, so the core certainly had some room to spare.  There is no documentation (that I could find) that Intel actually released anything faster then 3.6GHz, at least that I could find, but evidence suggests that they at least were thinking about it.  The picture is a Sandy Bridge Xeon in LGA2011 marked JKT EVEREST SS 4.4GHZ INTERNAL USE ONLY. JKT is short for Jaketown, Intel’s codename for the 32nm Xeon E5-2600 series.  That gives a very good idea what this processor was to be.  SS is likely to be a Single Socket (as often at those speeds getting dual systems working can be tricky).  Sandy was certainly capable of hitting 4.4GHz, with 4-core, and even air cooling, so perhaps these were samples for a limited OEM run, much like the previous Westmere X5698 processors.

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