The past few months we have been intrigued by an AMD GFX1250 target added to the LLVM codebase for the AMDGPU shader compiler back-end. GFX12 is RDNA4 and GFX1250 is presumably some “RDNA 4.5″https://www..com/”RDNA Refresh” part akin to GFX1150 having been for the RDNA 3.5 parts with Strix Halo / Strix Point. The prior LLVM code confirmed GFX1250 is in APU form factor but product details beyond that have been scarce. Today a new AMD GFX1251 target was merged to LLVM.
AMD GFX1251 is now present in the LLVM codebase as a new sub-target similar to GFX1250. The features enabled by AMD GFX1251 are very similar to GFX1250 just as there were a number of different GFX115x variants. GFX1250 introduces a number of new instructions, doubles the number of user SGPRs, and other improvements over GFX11 and GFX12.
The documentation patch confirms GFX1251 is an APU part just like GFX1250.
The AMD GFX1251 support was merged to LLVM Git today via this commit. I’ll keep monitoring for any more details on these unannounced revised RDNA4-based AMD APUs.