Question Can I run 2x8gb with 2x4gb

[Asrock97]

Hello everyone,

I have a skylake system with i5 6600k cpu, asrock k6 gaming z170 MB with ram support up to 64gb and 2×4gb gskill 2800mhz ram. I recently returned a faulty psu but instead of getting my money back (80€) I have to get something else. I was thinking of upgrading my ram by adding a 2×8 gskill 2800mhz (72€) or 2×4gskill 2800mhz (42€). Both the 2×4gb and 2×8gb ram are the exact same model as my previous ones. My questions are:

1. if I go with my 1st option and place the ram sticks in order 4-8-4-8 will my system be stable and have dual channel support in both pairs?

2. Will my purchase be reasonable cause many people think 24gb ram is an overkill - 16gb is enough. If both options are stable which one should I go with?

PS: I use the pc for gaming, emulation, development, and I also open some vm android/windows for debuging and testing.

 

[USAFRet]

The daily RAM question - Can I mix and match different RAM sticks and expect it to simply work.
As we see this here a dozen times a day.

The answer is a 100% maybe.
It might work, it might fail.

The only guaranteed solution is a set of RAM sold as a set.
Anything other than that - Maybe.

If you currently have 16GB, 24GB is not likely to help anything.
Are you currently running into that 16GB limit?

 

[Asrock97]

My current total is 8gb. I can upgrade to 16gb or 24gb. Why is this a maybe when the ram vendrors match, the ram model is the same, the ram clock matches, and the only thing that changes is the ram capacity? The 2×4 ram that I am currently using came as a set and so will the 2×8.

 

[USAFRet]

The 2 x 4 you bought as a set works.
A 2 x 8 you buy as a set works.

The 2 x 4 + 2 x 8 might not work together. Slightly different timings, different tolerances...

Being ALL the same has a greater likelihood of working together, but no guarantee.

 

[thunderkat351]

24Gb ain't overkill, some say is a bet when it comes to dual channel detection...
I have 2+2+4+4 1600mhz DDR3 on my 4790k running in dual channel without issues...
Will upgrade to 2x8 2400mhz someday, but I can tell you 16Gb is enough for gamming, but not entirely true, you actually need 16Gb to run Rise of Tomraider all max out, I have 12GB and if I don't turn setting to high (bellow ultra) my system start using virtual memory a lot during the benchmark due to the lack of RAM. 24Gb is a good sweet spot since you don't actually need quad channel. Get 4+4+8+8 totally worth it as long as you don't have issues with dual channel detection and the memory speed all work equally at optimal or close enough at least.