[SOLVED] X99-A upgrading 8gb to 16gb either not seen/booting errors/ oc fail

[Thrival]

Hi, I'm newly registered but have always been coming across this site for random pc bits.

I've been trying to find answers here and elsewhere to help me figure this out, so if I'm repeating a redundant thread I'm sorry. I'm overall inexperienced and probably have a question that's been asked plenty.

So, I've been trying to upgrade with another 8gb ram stick. Its the same stick as the previous 8gb I've been using. When I install it my pc either, has not seen the new RAM by win 10 but has by cpu-z, my pc doesn't boot and has one long beep followed by 2 short ones, or when I return to where I started by leaving only the original stick in it boots but shows overclocking error. Once the BIOS did recognize both sticks but the pc failed to successfully boot to windows. I'm missing something, either settings somewhere, installation, or maybe something faulty? From what I've read my mobo should support this. I've seen some things on increasing cpu strap or something labeled vv--- sorry can't remember, increasing the mhz for it...I thought RAM was an easier thing to install, what is possibly wrong?

Mobo: X99-A
CPU: i7 5820k
RAM: Corsair Vengeance LPX 8gb 288-pin DDR 4 SDRAM DDR4 2400 (PC4 19200)
The new stick is also this

GPU: gtx 970 if needed

 

[kerberos_20]

try reducing frequency to 2133
ram is sold in the form u got
either single stick, dual sticks, etc
mixing rams, even if they look same is never guaranteed to work

 

[Thrival]

Thanks I will try that tomorrow after work. So the safer idea wouldve been to look at them as a set, like a bundle of 2 8gb for example?