Hi Merecast, I am Rob, an independent and a 15 time and dual award MVP specializing in Windows troubleshooting and Bluescreen analysis. Please remember as independents we are not responsible for the development of Windows or the computer hardware and drivers. If you will work with me I will be here to help until the issue is resolved.
Did you reset the BIOS? Not just update it?
So I am a little confused. Are you saying the system is OK now with the old RAM but not the new here?
"I've tried the old sticks of ram which were working as expected, and the new ones on another pc and they also work at xmp 3200.mhz,"
If so:
What you are experiencing while trying to use the new RAM is not that unusual. Obviously, the MSI mobo has trouble stepping it up to 3200 XMP even though the specs for RAM on the B450 call for even higher speeds. So your recourse is to work with MSI Support and also check in their forums where others might be experiencing the same issue if it is a prevalent problem with that hardware.
MSI B450 Tomahawk MAX - Specifications
https://www.msi.com/Motherboard/B450-TOMAHAWK-M...
MSI Support
http://www.msi.com/index.php?func=service
MSI - Downloads (BIOS and Drivers)
http://www.msi.com/index.php?func=downloadindex
MSI - Forums
http://forum-en.msi.com/
MSI - Service
http://us.msi.com/index.php?func=service
MSI - Live Update On-Line
http://www.msi.com/index.php?func=downloadindex
MSI - Contacts - Set to North America - USA
http://www.msi.com/index.php?func=html&name...
If not: (it no longer runs well with either set of RAM)
If the PC is not properly functioning with even the old RAM then it sounds like you might have jarred something loose or caused some component to fail when you changed out the RAM.
Remove ALL power then reseat everything - cards, memory, cables (on both ends when possible), and the CPU and heatsink (with new compound) - remove and reseat - do not just snug.
If that does not help then you will need MSI Support for diagnostics and possible RMA.
Here to help,
Rob
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