Question Upgraded from 16gb to 32 gb with almost exactly same ram, but windows keeps crashing: IRQL_NOT_LESS_OR_EQUAL


Apr 20, 2017

Recently I have upgraded my memory kit from using 16gb(2x CMK16GX4M2Z3600C18). Beforehand I had already installed 2x CMK16GX4M2D3600C18. When buying the second set of ram I figured both would be the same as the timings and speed are so. However once my windows started giving the blue screen of death followed with IRQL_NOT_LESS_OR_EQUAL I took a look at the exact product name and I saw that they were identical were it not for the Z and D which are switched around. Now I am wondering what could be the problem that these two sticks are not able to run together? Or could it perhaps be that I got a faulty memory stick? I bought It new btw so is has not been used before. I am using an b450 msi gaming plus max motherboard which holds a ryzen 5 3600. Thank you in advance!
Ram is sold in kits for a reason.
A motherboard must manage all the ram using the same specs of voltage, cas and speed.
The internal workings are designed for the capacity of the kit.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards, particularly ryzen, can be very sensitive to this.
This is more difficult when more sticks are involved.
Test the second kit by itself to verify that it does work.

Best to return the unit and buy a single 32gb kit.

If you want to try to make it work, go into the bios with a working set installed and increase the ram voltage some.
Then install and try the second kit.
Sometimes that works.
When done,
Run memtest86.
It boots from a usb stick and does not use windows.
You can download the free edition here:

If you can run a full pass with NO errors, your ram should be ok.