Adding new ram with the existing one

[redwanavir]

I have a 8 gb dddr4 2133 mhz ram installed on my pc, now i want to add another 4 gb ddr4 2133 mhz ram making it to 12 gb of ram together. Is it going to work perfectly fine or will have any issues.

 

[cookiemania66]

To be honest? We cant tell you.
DDR4 ist a normed standard yes, but it is not guaranteed to work if you mix ram.
Companies are Sellings Kits like 2x4GB 4x4Gb 2x8GB [...] because they have tested these Ramsticks and they guarantee you that they will work together.
But if you mix Ram on your own it might work fine or it might work okay but not 100% of the time or even worse. Sometimes it wont work at all.

If you wanna make sure everything is working 100% then you have to sell your existing Ram and buy a new kit (there are only Kits with 4,8,16,32GB so you wont be able to get 12Gb) or you go high risk and buy 4Gb and it might work or not.