New RAM only works when mixed with old RAM?

freedom90

Honorable
Feb 8, 2014
11
0
10,510
Hi my motherboard is Gigabyte Z68-AP-D3 updated to the latest BIOS (2012 version)

My old RAM is 2 x 4GB G.Skill RipjawsX 1600Mhz and new is 2 x 8GB HyperX Fury 1866Mhz.

When I try the new RAM (single stick, double, different channels, all combos) I get a boot loop.
But when I mixed it with my old RAM, using it as a boot stick so to speak, it boots up - currently running 1 of each in different channels and it is showing 12GB (new 8GB + old 4GB)

The RAM is not defective as I've tried it on a different newer PC and it works and I tried the RAM from the new PC on mine and I still get the boot loop. (Same Fury RAM but 4GB version)

It seems unusual to me that the RAM works but won't boot with it, is there any way I can get it to work properly and is it safe to use it this way?

Thanks
 
Solution
check your motherboard manual to see if i has any hidden advanced menu's. i had an old gigabyte board that needed you to press shift F3 before it would show you the advanced timings...

freedom90

Honorable
Feb 8, 2014
11
0
10,510
Hi yes I didn't change any settings, I've played around more with it and it seems I can't use all 4 sticks together, only 3 of them, the 2 new one and one old so a total of 20GB and the old RAM has to be in slot 1, new RAM works in dual channel with both new and old RAM.

Strange one
 

freedom90

Honorable
Feb 8, 2014
11
0
10,510
I can't change anything in the BIOS except SPD which I set to 1600 then removed the old RAM but it still loops.

In CPU-Z it says:
DRAM Frequency 798.2Mhz
CAS Latency = 9 Clocks (even though the new RAM's specs are CL10?)
Old G.Skill = JEDEC #4 685Mhz CL9
New HyperX = JEDEC #5 837Mhz CL9

Would overclocking my CPU influence it in any sort of way? I have a 2500k at stock