Mix two type of memory

[pyl]

Hello, I have these modules installed on my pc F2-8500CL5D-4GBPI-B, but I wonder if I can add these F2-8500CL5D-4GBPK. I have seen that share latencies 5-5-5-15 and this voltage: 2.0v-2.1v, but I would if I could have a problem. Thanks for the help.

[Tradesman]

I've mixed these in the past on P45 mobo, you will want the latest BIOS and prob will have to add a bit of voltage to the NB (since it's 4 sticks) unless the BIOS is up to snuff, don't know what mobo you have

[pyl]

My motherboard is a GIGABYTE GA-EP35C-DS3R (Rev. 2.1)

[Tradesman]

Prob need the full 2.1 and maybe up to 2.16 on the DRAM voltage and still need to up the NB as that is what runs the MC (memory controller)

[TDIguy]

I also have a question on this topic.
Currently I have F2-8800CL5D-4GBPI. I'm wanting to add another 4GB pair but all I can find in stores is F2-8500CL5D-4GBPI-B.
I'm currently running my RAM at 1133MHz 5-5-5-15-68-2T timings as shown in cpu-z.
Will the 1066MHz set listed above be able to keep up or should I keep looking for an identical set to what I already have?

[Tradesman]

I'd either keep looking or may have to drop freq, maybe even down to 1066, if they'll even work together