How much memory does the PS4 use for the CPU and how much for the GPU?

Question

RAM

Please clarify the situation: in ps4 they say 8GB GDD5 memory, of which part is allocated for operational for the CPU.
As you know, video RAM is much faster than RAM for the CPU. If so, why do conventional computers use DDR3 memory for the CPU? Why does ps4 use GDDR5 for CPU? What is the difference between video memory and regular RAM?
I share two concepts: RAM for GPU and CPU. I used to think that GPU memory is faster (5.5 MHz) than CPU memory (1.6 MHz). What memory in ps4 is used for CPU and what for GPU?

Answer 1

I can only say that DDR3 or older generations (DDR, DDR2) are used for CPUs. The next generation of DDR4 should be released in December this year, or during the winter.
GDDR5 is based on DDR3 but designed for use in applications such as PS4. Accordingly, GDDR5 is the same as DDR3, but faster, especially for the PS4.
Here is the Wikipedia article about GDDR5. Therefore, I can say with confidence that this is a CPU.
PS4 CPU uses: 8GB GDDR5 (256-bit GDDR5 (operating frequency 5.5 GHz) with a bandwidth of 176 GB / s)
Unfortunately, I can not say the characteristics regarding video memory.

Answer 2

In addition to 8GB GDDR5, iFixit found another 2GB DDR3-2133 chip .
It seems to me that it is she who is used by the console OS, according to her needs.