• Now's your chance win big! Join our community and get entered to win a RTX 2060 GPU, plus more! Join here.

    Pi Cast Episode 3 streams live on Tuesday, August 4th at 2:30 pm ET (7:30 PM BST). Watch live right here!

    Catch Scharon on the Tom's Hardware Show live on Thursday, August 6th at 2:00 pm ET (7:00 PM BST). Click here!

Question 2 modules of ram don't work together

Jun 6, 2020
Hi guys, I'm kinda new but I already read some of the most reelevant posts about my issue and I haven't found a solution yet: I have a 1x8gb ram ddr4 2400 mhz working nicely. I bought 1x4gb ddr4 2400 mhz to add them to my computer but when I plug them both, correctly (clicking) it does not start. I switched slots, and it does not start. I tried with only the old one, and it bootsm I'm using ir rn. If I use only the new module of 4 gb and it works, but when I use them together they simply do not work. When they don't work the CPU and DRAM leds start flashing one after the other.
The curious thing, is that I tried using my brother's ram (1x8gb ddr4 2666 mhz) and it works fine with my new 1x4gb ram and with my old 1x8gb ram.
The problem only appears when I use my own 2 rams on my PC, because we tried my 2 modules on my brother's PC and they work!
So, the two modules can work together, my slots are fine as they work with my brother's ram, and obviously there's no CPU or PSU problems taking in to account that is working right now with only my 1x8gb old ram. What could it be? This gets me completely clueless.