well-known "internal thermal paste gate"
Huh? well-known? And yet
Google knows nothing about it.
mismatched ram is still mismatched ram, not talking about size.
different speeds/timings are never good, there is a reason why kits are offered for decades
Agreed. That said, way back in the day, they were sold in "kits" (pairs marketed as "dual-channel" with 2 sticks per pack) because every module was tested at the factory before leaving the factory, and best matched pairs were packaged together to ensure their speeds/timings most closely matched. This was necessary because raw materials were less pure and manufacturing techniques less precise than today. This resulted in the tolerances (deviance from publish specs) of the modules being less precise and consistent too. It also resulted in a relatively high failure rate. Not good.
These days, first, the production of the raw materials used to make the memory modules has improved such that the materials are MUCH MORE pure than yesteryear. Second, the manufacturing techniques used to make the modules have improved tremendously too. These improvements have resulted every module coming off the production line very precisely adhering to published specs. It also resulted in an extremely low failure rate. If you look around, it is pretty hard to find any RAM that does NOT have a lifetime warranty.
What all that means is factory testing (and matching) is no longer performed simply because it is not needed.
So these days, they come packaged in kits for convenience and costs. It is convenient for consumers because we can easily buy pairs that match in speed and timings and be certain they will work perfectly together. Packaging them together lowers costs because the logistics to package, inventory, market and transport pairs is cheaper than those costs for 2 individual sticks.
A third factor comes into play these days and that is CPU memory controllers are MUCH MORE capable of making two (or three, four, six or eight) sticks with slightly different deviations from published specs to play well together with no issues.
So, with manufacturing techniques so greatly improved, and memory controllers much more capable, today, if you buy sticks with the same speeds and timings as Waldorf recommends, even if they are from different manufacturers, odds are greatly in your favor they will work just fine.
I still recommend buying from the same makers, but on many occasion, we have used Crucial with Corsair, or Corsair with G.Skill and dual-channel worked just fine - in 2 and 4 stick configurations.
This is something I would not even attempt 20 years ago.
