CPU and RAM

[Rndm x sniperZz]

Will 64gb ram bottleneck a ryzen 9 3900x ?

[Jurrunio]

If you can use all of it, yes.

[GoldenLag]

No.

 

Also, thats not how Ram works.

[Bloody-George]

Simple answer? No.

 

When it comes to memory bottleneck on a CPU, it's usually not about capacity, but about speed. Is your memory fast (3200Mhz-4000Mhz)? 

Even if it's a bit slower (<2666Mhz), it also depends on the graphics card you use. Memory bottleneck is a bit complex, to be honest. Steve from Hardware Unboxed has shown that you can only feel the performance difference with slow memory in Ryzen if you have a high-end graphics card (say, RTX 2070 upwards). 

[eismcsquared]

Well if you're running 64GB of RAM on a 3900X you're running 4x16GB sticks which will put a higher stress on the memory controller than running only 2 sticks so you're probably not gonna be getting the same type of speed or latency you can from running a 2x8GB kit or 2x16GB kit. So from that perspective yes you can decrease the performance in certain applications (though not by much) by not having the same speed on that RAM as can be achieved with only 2 sticks of RAM.