> ... but not vendor (Dell, HP, etc.).
If you have any worries about compatibility issues: if you buy direct from Crucial.com and use their memory selector then they guarantee compatibility. You can also use their selector and then buy elsewhere by finding the off-site retail part numbers.
Crucial customer support taught me the "one weird trick"

:
"If you need to find the reseller number for any part on Crucial, you can do so by comparing that part with another (I would recommend one with a different price). Once the compare window pops up, the base (reseller) part number will be at the top of the specifications list."
Use the memory selector, find the RAM kit you want. Click the compare checkbox for it, then the compare box for some other kit. The word "compare" becomes a link to a new page that shows the retail part numbers like CT2K16G4DFD824A instead of the direct sales part numbers.