Direct3D feature levels discussion

DmitryKo said:
Well, logical ops in a render stage in Direct3D 11.1 do in fact require WDDM 1.2 - so they can't work in Windows 7 Platform Update, though unfortunately this is not reflected in the Direct3D documentation.
Click to expand...

Ah that makes sense; I should have researched a little harder and not taken the documents at face value. I'm just going to point out again that Direct3D 10 required little research... :smile: Also it's somewhat amusing (or sad...) that even Microsoft has trouble with these feature levels. :D
 
veemhqc286k5isfbl9i2.jpg


It's actually four levels 11_0, 11_1, 12_0 and 12_1 with a few options that span all levels (?) - namely, resource binding 3 tiers, tiled resource 3 tiers, conservative rasterization 3 tiers, typed UAV 2 tiers (?), and rasterizer ordered view - and in a D3D11 recap, some mandatory features on level 11_1 should be also optional on level 11_0 to make Fermi/Kepler owners happy.

BTW, back in February someone at Anandforums asserted that tiled resources are removed from Direct3D 12 since all resources are exposed through dynamic heaps...
 
Resource Binding, 6:40-9:30

At 9:05, Max talks about current market share for various RB tiers. I bothered to actually get Feb'15 Steam Survey stats into a spreadsheet, and assuming that
  1. Intel Haswell/Broadwell and Nvidia Fermi are Tier 1,
  2. NVidia Kepler/Maxwell are Tier 2,
  3. AMD GCN 1.x is Tier 3,
the numbers turn out exactly the same 39%, 44%, 17%.
 

Attachments

  • D3D12_RB_tiers.zip
    22.1 KB · Views: 7
Last edited:
Is there a summary somewhere that confirms which chips support which feature levels under D3D12?
 
DmitryKo said:
Resource Binding, 6:40-9:30

At 9:05, Max talks about current market share for various RB tiers. I bothered to actually get Feb'15 Steam Survey stats into a spreadsheet, and assuming that
  1. Intel Haswell/Broadwell and Nvidia Fermi are Tier 1,
  2. NVidia Kepler/Maxwell are Tier 2,
  3. AMD GCN 1.x is Tier 3,
the numbers turn out exactly the same: 39.0%, 44.3%, 16.7%.
Click to expand...

In Tier 2 64 is the max UAVs in all stage. But Kepler and Maxwellv1 only support 8. I'm confused.
 
willardjuice said:
was it merely implied because the cards were 11_0?
Click to expand...
Yep - seems to correspond with 48 MAX_COMBINED_IMAGE_UNIFORMS and 8 for each stage on latest 347.52 drivers (ARB/shader_image_load_store).

superjoeyprof said:
As far as I remember they wrote me years ago, that Kepler and Fermi support UAVs in the vertex, geometry, hull and domain shaders, but not support larger number of UAVs.
Click to expand...
They actually said Kepler does not support UAVs at all stages... though it seems like they just couldn't make Microsoft implement this as a option for level 11_0.
 
DmitryKo said:
Yep - seems to correspond with 48 MAX_COMBINED_IMAGE_UNIFORMS and 8 for each stage on latest 347.52 drivers (ARB/shader_image_load_store).

They actually said Kepler does not support UAVs at all stages... though it seems like they just couldn't make Microsoft implement this as a option for level 11_0.
Click to expand...
Apparently NVIDIA didn't enable UAVs at all stages because they don't support enough UAVs to meet the D3D spec (64 I believe). It is likely that devs can go through some sort of NVIDIA proprietary API to access UAVs at all stages (with limitations of course), just not in D3D. Though that is pure speculation.

Does anyone know if Maxwell v2 (e.g. GM204) shares this limitation?
 
Kaotik said:
Is there a summary somewhere that confirms which chips support which feature levels under D3D12?
Click to expand...

There was I slide posted on here with that information, but it was removed shortly after being posted. I happened to save it, but don't know if I should post it, since it and the entire post was removed.
 
Sinistar said:
There was I slide posted on here with that information, but it was removed shortly after being posted. I happened to save it, but don't know if I should post it, since it and the entire post was removed.
Click to expand...
Are you talking about the Resource Binding -tiers post or actual D3D Feature Levels? I saw the former, but haven't seen latter
 
Correction to the post above since I can't seem to edit from mobile....

The Wiki above does include Tonga (285) in the FL11_1 section but lists it as GCN 1.1 so I'm unsure of how correct that is.
 
Last edited:
pjbliverpool said:
Correction to the post above since I can't seem to edit from mobile....

The Wiki above does include Tonga (285) in the FL1_1 section but lists it as GCN 1.1 so I'm unsure of how correct that is.
Click to expand...
It's wiki, before the companies confirm it one way or another, don't trust it on this.
Yes, it could be right, but it could just aswell be wrong, anyone can edit it.
 
You must log in or register to reply here.
Back
Top