While writing this article we asked Corsair Memory what IC’s are used on the Dominator PC2-8888 modules that were reviewed in this article and why the prices were so high. One of the Corsair Co-Founders, John Beekley, replied back to LR on the subject and said we can publish verbatim what he said, so here it is.
I can try to provide some insight here – though I am not sure I can provide everything you are looking for. But let me give it a shot…
First of all, the simple answer – Micron 64Mx8’s are the RAMs used on all DOMINATORs at this point. And, on the 8500C5D, the RAMs used are the same RAMs that are used on our non-DHX 8500C5. From here on out, though, it gets more complicated, let me explain a little…
A variety of binning procedures are used to produce the ultra-fast products (6400C3 and 8888C4DF). These procudures include binning both at the IC level and the module level – that is, separating ICs into various performance bins prior to module assembly, as well as separating the modules themselves into performance bins after they are assembled. Yields on all these procedures are very dynamic, although we certainly wish they weren’t – different lots of material from the same manufacturer can have vastly different results, as the IC manufacturers tweak their process to improve yields to their own performance bins, which do not necessarily correlate with ours. And, of course, this screening and binning is all very labor intensive.
The 8888C4DF is the fastest of the fast – that is, we take the fastest ICs from our IC screening, build them into modules, then take the fastest of those modules and make them 8888C4DF’s. Next in the performance line is the 6400C3, followed by 8500C5D and 8500C5, then the 6400C4. Yields on all this stuff are very unpredictable, so I can’t provide a lot of numerical data here. A gross estimate would be that 5% of the ICs purchased yield 8888C4DF, another sub-5% yield 6400C3, and it moves on down from there.
Of course, the issue this raises is that for every 8888C4DF we manufacture, we need to manufacture nineteen other modules with the fallout. Not necessarily a problem, except that the fast Micron ICs are more expensive than other RAMs to begin with, so these nineteen other modules are relatively expensive to manufacture. They can not be sold at commodity pricing, unless they are “subsidized” by a higher price on the premium modules. So, these parts are really cream of the cream of the crop – very special parts, very expensive and difficult to produce, but worth it to many people who are seeking this edge.
As John mentioned in his comments back to Legit Reviews the yields on the IC’s used to make Corsair PC2-8888C4 modules are extremely low and that is the main reason they cost what they do.