Off the top of my head there is only like three manufacturers left. Micron being the only one not mentioned here.
Off the top of my head there is only like three manufacturers left. Micron being the only one not mentioned here.
As for who makes the best RAM, it changes from one generation to the next, and also depends on what you consider "best": you might be looking for chips that overclock well in a desktop, or that are least likely to suffer compatibility issues and performance loss when maxing out the capacity in a desktop, or maybe "best" might mean who has the lowest-power LPDDR for your phone.
The DRAM parts made by the big three largely all adhere to the same standards (thought not necessarily all supporting the same frequencies), with the most significant recent example being GDDR6X that was essentially a NVIDIA-Micron exclusive partnership. For the most part, it's the latest iteration of DDR (desktops and servers), LPDDR (handhelds and low-power laptops), GDDR (GPUs), and HBM (more expensive GPUs).
This reminds me of HDDs and SSDs, though I've always found RAM to be generally reliable or obviously bad, while storage can look ok for a while before it fails.
Whether that matters much is debateable - maybe they get higher yields as a result (since more chips are sufficiently performant to be useful) but JEDEC specs seem pretty generous relative to what you can achieve on consumer platforms, so I somewhat doubt much RAM is thrown out because it's too slow to meet spec.
It's pretty random, though. Back in DDR4 days Samsung produced the best memory (B-die) and it wasn't particularly close - near-DDR5 speeds with lower latencies. At the same time, some of their other dies (I guess from other fabs?) was absolutely awful.
Again, I don't know how much that translates into profit though, since the performance user market for RAM is probably a fraction of a fraction of the overall memory market.
Now with DDR5, Hynix's A-die is considered the best option.
Less impactful in DDR5 because they made it a design goal to have more "ranks" by default, though it does still have a small performance benefit.