Hi, I am in a bit of a dilemma. I was planning on upgrading my ram to some G. Skill snipers when I found them on sale. As I was about to put the G. Skills in, I realized the the 4gb of corsair I was planning on taking out for good had identical stats. Both 1.5v, ddr3-1333, PC3-10666, 4gb, and 9-9-9-24.
Would this setup work? Also, how would I place the ram on my board? Put the G. Skills in the first two slots and the corsair in the 3rd?
If this matters, I am using an MSI P67A-G45 (B3) with an intel core i5 2500k.
If you still have the owners manual that came with the motherboard it will tell you how to place three sticks (if it is alowed) in the ram slots. I would put the G.Skill sticks in the blue colored slots and the one Corsair in the first black slot , or the two G.Skill in the black slots and the one Corsair in the first blue slot. But hopefully you have the owners manual and you can see for sure how to do it. It's not like it will blow up if it's wrong , it just won't work.
As a rule of thumb you never want to mix and match ram, but beggers can't be choosers so sometimes you make do with what you have.
As long as they are all rated for the same voltage and speed they should work, it won't damage your system to throw an extra stick in, but you may become unstable if your board doesn't like the combination.
Like I said with the thing not blowing up all you can do is try it and see what you get. Run the system with 8gb of ram and gage the performance and then add the 4gb to the mix and see what that does for performance.
Would I see a performance decrease if I use all 12 without dual channeling compared to just 8gb and dual channels?
This would depend on your usage of the computer. In gaming probably. In normal desktop apps probably not. All you can do is test it out to see if you like the difference. Most of the time 8G ram will be plenty.