Question Can 16gb ram be added with preinstalled 4gb to get 20gb RAM?

Feb 29, 2020
I bought a HP Probook 450 G6 recently and it comes with 4GB DDR4 RAM. I plan to add a 16GB stick in the other channel and I am aware the board supports a maximum memory of 32GB RAM.

I did some research on having different RAM sizes and I found out that Intel's FLEX MEMORY feature allows different memory sizes to be installed such that in a case like this 4GB on channel A and 4 GB on channel B runs in dual-channel mode while the other 12GB from channel B works in single-channel mode.

I would like to know if there are any issues that may be encountered with this setup. Kindly share your experience.

I don't want to add 2 * 8GB as this would require me to get rid of the 4GB unnecessarily. Besides, if I want to upgrade later, I would have to get rid of atleast one of the 8GB sticks. I also don't want to add 2 * 16GB now due to cost constraints.
Jul 19, 2018
I have had a similar thing happen to a friend of mine. He had 1 8GB stick in his HP Pavillion, and he wanted some extra RAM. I happened to have a spare 4GB stick lying around and it works. He now has 12GB of RAM.

There's a chance that it might work, but its not a guarantee. It worked for my friend because they were both HP branded sticks and the same speed.

I also recently added an extra 8GB DDR3 1600MHz stick to pair with HP's 8GB. They were both the same speed, and same capacity. They worked perfectly in dual channel mode.

So if you really want it to work, try the same capacity and speed. But as you mentioned, you don't want to have two 8GB sticks. It's worth a try though with your 4GB and 16GB module