Ram Compatibility Issues

[rl123456789]

Hi, I am facing some Ram compatibility issues and was hoping someone could help.

my computer setup is as follows:
1. GIGABYTE GA-F2A55M-S1 Motherboard
2. 1 Terabyte Hardrive
3. G.SKILL Ripjaws Series 4GB 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9S-4GBRL
4. Rosewill Slim MicroATX Computer Case with ATX12V Flex 300W Power Supply, Black/Silver R379-M
5. Stock cooler fan
6. Windows 8.1 64bit.

So I was trying to upgrade my ram with the following 8GB ram stick:
G.SKILL Ripjaws X Series 8GB 240-Pin DDR3 SDRAM DDR3 1866 (PC3 14900)

but when I inserted it into my motherboard with the other ram stick that was already there (the 4GB Ripsaw one specified before) it caused a lot of issues. After I inserted the Ram stick the computer would often not boot to the windows screen. When it did boot to the windows screen it would often end up crashing windows and I would receive a screen stating that windows had crashed and needed to be rebooted. The farthest I've gone would be the login process before the computer crashed and stopped functioning. I know the issue is the newly added ram stick because once I remove it and only keep my original ram stick, the computer runs fine. Similarly, if I keep the new 8GB ram stick in but remove my older one, it also works fine. It only decides to not function when both ram sticks are in there together.

With that kept in mind it leads me to believe that the reason why it's not working is because the two ram sticks are incompatible. I really wanted to have it so that my computer had a total of 12GB of ram but I'm not sure if that's possible. Could someone tell me what I'm doing wrong and the best solution forward? Also If I must return the new ram stick that I bought, which one would be compatible with the older one that I already have? Thanks!

 

[brispuss]

As there are only two DIMM slots available on the motherboard, DIMM's inserted into each slot will make the system attempt to run the memory in dual channel mode automatically.

Dual channel operation usually requires DIMM's to have similar memory chip architecture, same capacity, same voltage requirement, same timings, same speed. But in some cases dual channel operation will work even when there are differences between the DIMM's. However, whether the DIMM's will work in dual channel mode or not is dependent on the design and sensitivity of the memory controller. Some memory controllers are very sensitive and require more closely matched DIMM's for successful dual channel operation.

In this case, it seems the combination of the 8 GB 1866 DIMM and the 4 GB 1600 DIMM are incompatible to the memory controller (due to different capacities, different speed, and probably different timings as well) which in turn causes issues. So this particular motherboard seems to have a sensitive memory controller.

To be certain of compatibility, recommend purchasing a matched pair of DIMM's for dual channel operation, such as 2 x 4 GB or 2 x 8 GB modules. The single 8 GB 1866 DIMM could be returned.

Alternatively, and it is a slight gamble, purchase another G.SKILL 8 GB 1866 DIMM the same as the first 8 GB DIMM and try these two together and hope the memory controller will accept these DIMM"s and run them in dual channel operation. But there is no guarantee this will work.