I have an iMac 27" late 2015 / i7 with 8GB Apple Ram.
Apple memory runs at 1867Mhz fine. When I add two 8GB OWC 1867Mhz RAMs, they all run at 1600.
Any hints what the problem could be?
- Apple RAM: 1867
- I tried just the OWC's: 1600
- I tried just OWC's in slots 1&2, and in 1,3: 1600
- I tried Apple RAM in slots 1 & 2, OWC in 3 & 4: 1600
- I tried Apple RAM in slots 1 & 3, OWC in 2 & 4: 1600
Thanks,
Arthur

Apple memory runs at 1867Mhz fine. When I add two 8GB OWC 1867Mhz RAMs, they all run at 1600.
Any hints what the problem could be?
- Apple RAM: 1867
- I tried just the OWC's: 1600
- I tried just OWC's in slots 1&2, and in 1,3: 1600
- I tried Apple RAM in slots 1 & 2, OWC in 3 & 4: 1600
- I tried Apple RAM in slots 1 & 3, OWC in 2 & 4: 1600
Thanks,
Arthur
