I'm a programmer. GDDR5 is enough.

While GDDR5 will certainly be enough, GDDR6 will be more practical by then. Higher density chips (cheaper, smaller mainboards) and the prospect of falling costs instead of rising costs (as PC will switch to them too, meaning only low-end rebrands will still use GDDR5 in a couple of years, making their production more expensive due to low volumes) are the main arguments in their favor.

That website isn't benching games.
Synthetics has always been a strong point for AMD GPU's for various reasons.

I don't consider the Xbox One to be vastly different to the base PS4 anyway.
And I would also make the statement that the "Xbox One gives the PS4 a run for it's money".

Because outside of lower resolutions, a few scaled effects and sometimes lower framerates, they often provide very similar experiences.

If average gamer upgrades to a 4k TV lol!

You could just as well be a house maid, it would carry the same weight to this topic.

GDDR6 will be released in 2018 (the Volta cards should already be using it) and HBM2 is already out.

When we are looking at new consoles with games targeting 4k native resolutions, either an absurd amount of GDDR5 DRAM would be necessary (with the ram prices being at an all time high) or the simplest answer would be actually embrace either HBM2/GDDR6, using smaller dies, lower power, lower cost and much higher memory bandwidth. Even more when these new consoles would need to be around by 2025+

So even if theoretically there would be an amount of GDDR5 that could do the job, it's not possible when taking into consideration the costs, size and power draw of the consoles as well as next gen gaming needs.

You don't know what you are talking about. You don't understand how the memory in consoles works. Please educate yourself before posting BS.

are you trolling right now? no need to reply to me unless you have something worthwhile to say, thx

The stuff you write is ridiculous. It doesn't meter if you are using GGDR5 or GDDR6/HMB2 for the 4K resolution! It's not like that you need more ram if you are using GDDR5 instead of GDDR6.

I'm trying hard not to insult here, so I'll attempt to stay positive and on the point...

Higher resolution assets require higher memory bandwidth.

GDDR6 and HBM2 provide much higher bandwidth for the same amounts of RAM when compared to GDDR5. Also, the die sizes are smaller, meaning lower costs and lower TDP (more efficiency) for higher performance.

At the same rate, whenever 4K+ resolutions will be used, an even higher memory bandwidth will be necessary, thus requiring yet another jump in RAM efficiency.

Kid, as I said before. You don't know anything about economy and technology.

Consoles are not a PC. PS4 doesn't have 8GB GDRR5, it's actually has 16x0,5GB of unified memory. That's why the bandwidth is so high (176GB/s). 16GB of GDDR5 will be enough to run all games in 4K/60 if needed.

You are also completely ignoring the fact how difficult and costly it is to implement HBM. GDDR is just slapping modules on a PCB. HBM is using complicated interconnects and thru-silicon via's to connect delicate parts together. The kicker is that the company that can handle that isn't the same as the one that makes the HBM itself. So a high-end GPU has to go through 2-3 different companies possession which is a lot of incurred cost.