Question Is using "Infinity Cache" for Navi 2X a good move?

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TheRookie

Junior Member
Aug 26, 2019
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AMD's previous flirting with exotic memory has been a disaster thanks to high prices and limited availability (think HBM2 in Vega and HBM in Fiji).

With Navi 2X using plain old GDDR6, AMD can get it from anywhere and inexpensively.

NVIDIA is stuck with getting relative expensive GDDR6X memory from Micron.

On the other hand, Infinity Cache has likely ballooned the size of the die and TSMC's 7nm is capacity constraint.
 

JoeRambo

Golden Member
Jun 13, 2013
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Where I expect the gains to be less pronounced? Lower resolutions. At 1080p, it should only need 32MB to be just as useful. That extra 96 MB is just a drop in the bucket for texture caching. It might help in RT tasks.

Let's not underestimate the "RT" part of things. By 2020 framebuffer caching and streaming and chunking is solved problem. Things like BVH expand the working set for chip in ways other "buffers", don't.
You have "tree" structure that no matter how well you build it will have way more random access patterns than say framebuffer, vertex or texture block in memory. You are basically chasing tree node pointers around in memory and if full structure does not fit, bad things happen to the rest of the chip.
So AMD is throwing big chunk of SRAM to help their 1st gen RT hardware and other workloads, that is probably the reason why all chips have full 128MB ( even if SRAM is easier to yield, still a conscious decision to not nerf to say 96MB ).

The real question here is how much concurrency the chip can have between different workloads. NV can execute graphics + RT + tensors for DLSS at same time, can AMD 1st gen achieve something? Would be great to extract the most from these caches.
Also caching is a policy, there is some maneuvering a good driver team can do for performance for existing and new games ( like "let's pin BVH that is not more than size X for this game in cache" ).
 

IntelUser2000

Elite Member
Oct 14, 2003
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Infinity Cache is going to be the way forward for AMD's APUs to really shore up the bottom end of the market in a big way and pull away from Intel's offerings.

Not really, unless they use alternative technologies such as eDRAM.

SRAM scaling has been slowing down few processes ago. The 5nm TSMC process only affords 20% SRAM reduction in the Apple A14 SoC. SRAM is now trending worse than logic in terms of density.

Discrete GPUs will always be faster and needed because it has the same limitation. What faster iGPUs allow you to do is reach greater masses to be able to play games.

The increase in performance with iGPUs haven't been free either. We went from a CPU-independent iGPU costing $5 to end users to needing a CPU upgrade and costing $30, and maybe even a fast RAM to get the full benefits.

Also we went from playing at 1024x768 resolutions with no AA/AF at 60 fps to 4K resolutions at 60 fps with AA/AF, or 1440p resolutions at 100Hz, and 144HZ or even 200Hz for 1080p resolutions.

Though I never had beyond a 1080p monitor, and currently I'm using one with 1280x1024 resolution, I have seen GTA V running on a 1440p monitor and it looked gorgeous. I can see why if you are willing to spend money you'll go for 1440p or higher resolutions.