Why I think the R9 Fury X only has 4GB of VRAM

[PM97]

I was just thinking about the R9 FuryX and why it only has 4GB of VRAM. The benchmarks seem to show it performs best when playing at 4K resolution, otherwise, it is (very slightly) behind the 980Ti. I think this could be because, they expect those who are going after 4K to Cross Fire the cards, which makes sense. This is because, with DirectX12, the VRAM of multiple cards will be added together. So more may not be necessary. Now, one could argue that there are benefits for having 6GB of VRAM for things like heavily modded Skyrim but at this point price becomes a factor. Currently the FuryX can compete with the 980Ti as it is similarly priced, has similar performance and runs a bit cooler. If they did add the extra VRAM, it wouldn't affect the benchmarks as much and it would drive up the cost, potentially decreasing the sales. I think, based on this, AMD made the right decision to go with 4GB. I just hope Cross Firing 2 cards doesn't result in vertical screen tearing.

[minibois]

But don't forget that the Fury X has a watercooler installed standard, so that might be annoying when you want to Crossfire them

[inflictedpotato]

The reason that the Fury X has 4GB is primarily due to chip yields and technical feasibility. If AMD could have given us 6 or even 8GB, they would have. 

[BananaNinja]

the real reason is because there is a technical limitation to this current version of HBM which makes it challenging to incorporate more than 4GB at this current point
HBM 2 will allow up to 8GB
Remember this is a very new technology, folks

[Thorium19]

I think it was more technology based why there is only 4GB of HBM on it, as they could only manufacture 1GB stacks in large quantities.

[Oshino Shinobu]

Stacking of vRAM is not confirmed. Even if it is supported by DX12, it also requires the developer to implement it. 

 

The RAM on the Fury series is also HBM, which can help at higher res, but it's limited in the possible sizes right now. 

[Wauthar]

I think it's more like that HBM is a new technology that is very expensive with low yields. At this moment, AMD was only able to put 4x 1GB on the chip because higher capacities aren't there yet.

[Grrizz]

As other have said its really down to technical limitations, the DX12 stacking probably wont be common because its being left to devs to implement and even if a handful of games implement it and get it running acceptably (which will likely be no small feat being the GPU devs cant even get SLi/CF running properly most of the time) it'll probably be a long time (after the next generations out) before we really see it, after all how many Mantle games use it?

[PineappleHolidays]

It's a technical thing, not decision.

if they could have stuck 8gb they would have.

[Sauron]

The true reason is that they physically could NOT fit more in the card because of limitations of the first version of HBM. This should be fixed in later iterations.

 

They were most certainly not counting on the dx12 memory stacking feature, because that's something developers need to specifically implement and I really wouldn't trust most of them with that.

 

Besides, as of right now 4gb are plenty even at 4k. By the time they are not enough anymore, people going for 4k will most certainly have already upgraded. I am a bit of an exception because I don't care that much for quality settings whereas I do care a lot about resolution, so if I had one it would probably last me longer than for others. That said I still try to stick to the ideal 3-year upgrade cycle.