Originally Posted by diedo
as the title said I was trying to OC my 9900K and I couldn't get it more than 4.9Ghz stable, in the mean time I was suspecting ram issues but it passes memtest, anyway I'm also going to add more ram so do I buy a 2x16 rams or add another 1x16GB
It's alwas better to do dual channel. You might see a significant change in fps in the more demanding gamessuch as AC Oddysey.
I don't think that it matters wheather you have a different brand of the RAM as long as it's the same efficiency for example: 16 GB 3000 Mhz and 16 GB 3000 Mhz.
Though before you insert the RAM check closely wheather your motherboard supports such frequency.