A Suprising Discovery Inside The Steam Deck’s APU
Following a superb Youtube video from HighYield not too long ago, we’ve learnt two issues concerning the design of the APU used within the Steam Deck LCD model:
- The Steam Deck APU (codenamed Van Gogh) has unused elements with much more cores. And it is extremely possible that the very same APU was additionally used for the Magic Leap 2 AR glasses, which makes use of such cores.
- The Steam Deck APU used within the OLED version often is the first chipset completely made for the Steam Deck platform, with a smaller footprint not simply because of the 6nm lithography, however as a result of the unused cores have been eliminated.
Now that you already know what we’re going to take a look at, let’s see the entire story in photos.
The Steam Deck APU
The Van Gogh APU combines a high-performance CPU with AMD RDNA 2 architecture-based GPU cores, delivering good graphics and processing capabilities with a deal with vitality effectivity. It makes it candidate for handheld units just like the Steam Deck.
Because of the detailed pictures of Fritzchens Fritz we now have a transparent concept of how the Van Gogh APU is break up, in particulars.
One other angle:
The Reminiscence and CPU Cores
As anticipated we are able to see the reminiscence controllers simply subsequent to the CPU cores. There are 4 CPU cores, and so they all share the L3-level cache which is simply in-built between the CPU cores.
To date, nothing stunning, and you may see how small the CPU cores really are in fashionable processors.
The GPU
The RDNA 2 GPU Cores
The GPU cores are separate in 4 WGP (workgroup processors).
They function a number of sub-parts:
- A number of layers of cache
- 4 items of 32 ALUs (Arithmetic Logic Items) for vector processing
- 2 items of 4 TMUs (Texture Mapping Items) along with Ray-Tracing items.
Whereas it might come as a shock, the Steam Deck can really do some Ray-Tracing whereas it’s pretty weak in that regard. It has nonetheless been applied to help just a few video games resembling Doom Eternal.
There’s some further GPU Misc elements that most likely deal with many different issues (reminiscence switch, encoding, your guess is pretty much as good as mine) that area a big quantity of die area.
After all, there are additionally further connectors on the fitting facet of the chip for numerous I/O ports, like SATA, USB and extra.
But it surely nonetheless doesn’t clarify what we’ve right here on the center proper facet of the chip.
The Mysterious elements
There’s an element that represents virtually 15% of the floor that’s fully undocumented.
It incorporates further cores, and the heteregoneous form. 14 further cores to be actual.
Seems, this half is further GPU cores, and it appears to be fully per the description of the chipset used in the Magic Leap 2 AR glasses.
You may see the specs beneath:
| Class | Magic Leap 2 | Steam Deck |
|---|---|---|
| GPU | AMD RDNA 2 2 RB+ (Render Backends) Max Gfx frequency capped at 1.1 GHz. |
AMD RDNA 2 Max Gfx frequency 1.6GHz |
| CPU | AMD 7nm Quad—core Zen 2 x86-64 core (8 threads) 14 core laptop imaginative and prescient processing engine (CVIP) Max CPU frequency 2.4 GHz Cache sizes: 512kB L2 per core and 4MB complete L3 cache. |
AMD 7nm Quad—core Zen 2 x86-64 core (8 threads) CPU frequency 2.4-3.5GHz Cache sizes: 512kB L2 per core and 4MB complete L3 cache. |
As you may see the 14 cores appear to be clearly talked about within the specs sheet of the Magic Leap 2, and are used for picture processing. Whereas among the frequencies used internally between the 2 chipsets are completely different (the Steam Deck makes use of increased frequencies) it’s believable that they share the very same structure, and that these 14 further cores seen on the Steam Deck LCD APU have been really made for the Magic Leap 2 within the first place.
Variations between the LCD and OLED Steam Deck APU
The video continues by explaining that the distinction in floor space between the Steam Deck LCD APU and the brand new model as discovered on the newer Steam Deck OLED APU are pretty giant: the brand new APU is far smaller in dimension.
That is nonetheless not per the type of progress we count on from the TSMC course of when shifting from 7nm to 6nm, as many of the enhancements in density don’t broadly apply throughout the board however just for particular logic circuitry.
So the speculation, that continues to be to be confirmed, is that the Steam Deck OLED APU is definitely made particularly for the Steam Deck this time, and does away with the 14 cores utilized by the Magic Leap 2 since they aren’t wanted on the Steam Deck.
This appears to match the massive floor discount noticed within the chip space on the brand new board. At that time limit, Valve would have been capable of predict what number of items they might count on to promote based mostly on earlier shipments, and order absolutely custom-made chips for his or her new Steam Deck revision.
This additionally feels like Valve can have alternatives down the street to additional customise what goes of their Steam Deck 2 platform, vs utilizing extra generic chip designs from AMD that will not match the decrease energy enveloppe focused by the Steam Deck.