can i get dual channel with mixed ram sizes?


Feb 9, 2018
my friend has a laptop that has a single 8gb stick of ram and an empty slot. if they put in another 4gb stick would they get dual channel?
HP Notebook - 14-cf0013dx
this is the model of the laptop if that helps


Think of ram upgrades as you were to buy a pair of shoes. You ideally want to work with the exact same stick of ram you currently have to evenly load out the slots and ensure you're efficiently in dual channel mode. Unbalanced and mismatched sticks will only lead to more troubleshooting or worse, BSODs that lead to no end.

I would suggest you look at a ram kit and before you upgrade the ram, make sure you're on the latest BIOS update for your laptop.

I agree with this answer, to a point. Many people have been in your shoes and many have made the exact upgrade you have made without issue. Then again many others haven't and we, Linus, Anandtech and other forums see those people that don't understand why a seemingly identical(same speed, voltage, timing, size and brand) RAM module won't work, causes system instabilities, crashes/ freezing, blue screens of death etc.. The why is very complex but suffice to say they aren't identical and compatibility is not guaranteed unless they were purchased in a kit.You take that a step sideways with an obvious difference so you just raise the possibility on incompatibility. Keep it simple sir and purchase a dual channel kit. That's but one manufacturer you can buy from. Corsair, Kingston and G. Skill are just a few other dependable brands. That single stick can be saved for troubleshooting should your new kit ever fail. Life happens...

The performance difference between dual and single channel RAM varies depending on what task is be performed on the PC. Why do you need another stick? Have you been using 90% or more of your existing RAM?

A 4GB module can be added and it just might work but you know that question posed by Clint Eastwood, do you feel lucky? Well do you? Pud?

Is the chosen solution over here incorrect?

My old Lenovo Ideapad Y470 only had a stick of Crucial 4GB RAM. My brother gave me a spare Kingston 2GB RAM stick which I installed it operated fine with no issues. I verified the RAM (a total of 6GB) was operating in dual channel mode by using a program called CPU-Z; in the memory tab the "Channels #" field stated "Dual" which meant the RAM was operating in dual channel mode. Prior to installing the 2GB stick of RAM, it stated "Single".