motherboard or memory issue? (1 out of 4 slots working atm)

[Seaneezy]

Pretty recent build with MSI 970 gaming motherboard. I have 2 different brands of RAM, both compatible with my PC. I had post issues about a week ago and I had to rebuild. Up until now I have had 4gb of memory in my first slot(the only one that would let me post). I got another 4GB in the mail today and found that my 2nd slot won't let me post if it has memory but the 3rd and 4th don't (strange because they didn't a week ago). So I booted up and found that my PC didn't register that the slots are being used. It only says that there is one used slot in task manager and 4gb total. I have rebooted 3 times and each time undone the RAM from the slots and put it back in to make sure it was all the way in.

 

[geofelt]

Ram is sold in kits for a reason.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards can be very sensitive to this.
That is why ram vendors will NOT support ram that is not bought in one kit.
Although, I think the problem has lessened with the newer Intel chipsets. Still,
it is safer to get what you need in one kit.

If you want to pursue it, memtest86+ is the gold standard for testing ram.
Test each stick individually and in each slot.
Working ram will have NO errors for a full test.

All ram needs to be managed to the same specs so you could try giving the ram a touch more voltage.

 

[Seaneezy]

I'm so smart.... I unplugged the ram i final time and replugged it in and heard the 2nd click I didnt hear before. Confirmed 180 IQ