New PC won't start, can't figure out if it's a mobo or RAM issue

[j.lodberg.hansen]

My friends PC: https://pcpartpicker.com/list/DrhJcc

My PC: https://pcpartpicker.com/list/CBgMjc



My friend just bought a new PC with the parts as seen above. The first pair of RAM he received he RMA'd because the computer would only start up with one of them in.

Now he received another of the same pair from the RMA and the pc sometimes works when he tries to start up - and sometimes not.

We've been trying out his RAM in my PC (build seen at the end of this post) and they work fine. When we try the RAM from my PC in his, his PC also works fine.

So basically, my PC works fine regardless of which RAM are in it. Meanwhile his always works with the RAM from mine, but only sometimes with his own RAM in (and usually only with one of them). When it doesn't work, nothing shows up on the monitor but his coolers seem to start up fine and all the lights are on.

Would you say if this is a RAM or Motherboard issue? Or maybe something completely different?

 

[panathas]

That RAM doesn't appear to be stable in your friends PC. You should update the motherboards UEFI/BIOS especially if it hasn't been updated before. There seems to be a compatibility issue that should get fixed with a BIOS update. The Ryzen platform is new and there were many RAM issues that got fixed with BIOS updates. If that doesn't work you should log into the BIOS and lower the RAM clock speed. 3000MHZ may be too much for that specific motherboard/CPU combo.

 

[Zerk2012]

Go into BIOS when his PC boots and set the memory voltage to 1.35.

 

[Danra]

Some AMD motherboards will not run at 3000MHz RAM. If it is set at that, reduce the speed.