In a livestream, Eric van Beurden and Michiel Berkhout from MSI Netherlands discussed the wide array of Z490 motherboards that MSI built to host the upcoming Comet Lake-S CPUs. In addition to discussing the motherboards, however, they also touched on the CPUs, most notably their quality levels, as spotted by VideoCardz.
Of course, what this really is is a judgment of Intel's binning methods. MSI tested a handful of Intel Core i5-10600K, i5-10600KF, i7-10700K, i7-10700KF, i9-10900K and i9-10900KF processors and determined how well they run at different clock speeds and voltages.
MSI evaluates the chips and places them in one of three categories, based on quality level. Mid-tier Level B chips meet expectations, and Level A chips exceed performance expectations.
The execs said that Level C chips are "below the standard," and around 30% of Comet Lake-S silicon fit this category, according to MSI's testing. (Intriguingly, the percentages don't add up to 100%.) But don't panic; this only affects you if you want to overclock your CPU. A Level C chip that made it through Intel's Q&A is almost certainly still good enough to perform as advertised -- you just won't be able to hit high overclocks with it.
According to MSI's data, i5 and i7 chips rarely come with top-quality silicon. If you purchase an i9-10900K(F), however, there's a greater chance you'll get a chip that overclocks tremendously. Out of the batch that MSI sampled, 27% of these CPUs used the highest quality silicon. Of course, that doesn't guarantee your chip will achieve huge overclocks, but, alas, such is the nature of the silicon lottery.
MSI also shared a slide (above) detailing the average voltage required for running stable at different clock speeds. It seems that the i5 parts require higher average voltages to run the same clock speeds, whereas the i9 chips require a lower average voltage at all clock speeds.
If you're in the market for a Comet Lake-S i5 or i7 chip, you shouldn't expect a lot of overclocking room, based on MSI's data. But it's not surprising to see Intel apparently reserving its best silicon for the i9 chips.
If Intel were to use the silicon from an i5 quality chip in the i9s, that CPU would need a higher core voltage to run stable, which in turns leads to higher power consumption and higher thermals. Those two things are exactly what Intel needs to avoid, given that it is squeezing every last bit of performance out of the 14nm process with Comet Lake-S.