Manufacturers of RAM, specially gaming RAM, sell 64GB kits of RAM (4 x 16GB modules), and also 128GB Kits (8 x 16GB modules). In one of the reviews of 64GB G.Skills Ripjaws V kit, one customer says that:
G.Skill and most memory makers do not guarantee two kits of RAM to work together. So if you are hoping to use two of these kits on a MB that supports 8 x 16GB RAM, you would be better off buying a single 8 x 16GB kit instead.
What is the meaning of not giving a guarantee that two 64GB kits will work together? I am asking since two 64GB kits like the ones mentioned would cost $510, whereas a single kit like this would cost much more, more than $600.
My question is, is it risky, might not work most of the time or sometimes, or causes problems only when overclocked? If anyone with experience can answer it would be helpful. I am assuming the motherboard can CPU can take 128GB RAM.
My own experience and search says the setup of two kits should work, since I have seen modules purchased at different times work together (one original, and second as update later, same manufacturer but different series). If speeds are different, system adjusts to the lower speed. If the configuration is not optimal, like 2 modules in slot 1A and 2A instead of slot 1A and 1B in dual channel gives warning on boot but otherwise works fine. Also kits are matched to give best performance but separately purchased modules of RAM should work fine, maybe a little slower, according to my understanding.
So is it a high risk purchase, low risk purchase or best avoided and my understanding is incorrect?