I bought a ThinkCentre M75s through ebay.ca It came with a single 8GiB stick of RAM. I wanted more! DDR4 RAM is pretty cheap these days. I bought 8GiB (to pair with the original stick) and 2 x 32GiB. Lots! I got it from amazon.ca - DDR 32000MHz, as per the "psref" documentation for the computer - DIMM, not SODIMM, since it is a desktop - fairly low latency When I got it, I could install it in my machine but I could not reassemble the machine. I needed "low profile" DIMMs. Not mentioned in the manual. So I have initiated a return with Amazon.ca. They would even come to pick the 2 x 32GiB units up, but that's no use since they require me to drop the 8GiB DIMM off at a Purolator establishment. I have now tried to order low profile versions. This time, Canada Computer was cheaper. They offered free shipping for the 32GiB x 2 but $10 for the 8GiB. I asked if the 8GiB could piggyback on the free shipping for the other DIMMs: no. Shipping from memoryexpress.com was more expensive. NewEgg.ca didn't seem competitive. So I'm not going to buy a mate for my 8GiB. So this is what I bought for $159.99: <https://www.canadacomputers.com/product_info.php?cPath=24_311_1326&item_id=195989> I think I paid roughly the same for 64MiB of RAM for my first PC clone in the mid 1990's.