Yes, using two distinct memories with different speeds, brands, and timing can influence performance.
Yes, using two distinct memories with different speeds, brands, and timing can influence performance.
I own a dual memory channel mATX motherboard and previously had only one 2400MHz DDR4 8GB RAM from Samsung. Recently, I realized that 8GB isn’t sufficient for the tasks I perform, so I added another 16GB RAM stick (single unit). I think it was likely Team Elite with a 2666MHz speed. I’m aware that overall performance will still run at 2400MHz because of my slower RAM, which is fine—I can always upgrade later. Noticing this, I observed that certain games I play use significantly less RAM than what I have (24GB, plus 8GB and 16GB). For example, Microsoft Flight Simulator 2020, which can require up to 13GB in some benchmark videos, only uses about 8GB on my system, even when minimal programs are running, using roughly half of the available memory. This leads me to suspect that some games might not fully utilize my RAM and are only accessing a small portion. I’m not an expert on RAM, so I’m unsure if this is due to differences in brands, timing, or speeds. Since most people buy identical RAM kits, it’s possible the issue lies with compatibility or configuration. If anyone has insights, it would be helpful.
Typically the board should handle both DIMs using the slowest frequency and timing in the system, functioning properly. I actually have 2,366 and 2,320 stick configurations, but I've boosted the slower ones to match or exceed the faster ones. On my older server PC, I'm using three 4GB and one 8GB DDR3 modules. It should perform as expected—perhaps try Memtest86 to check for issues. Also, running games in various settings will change RAM usage.