Thread by @Gavavva

Ok, how are we all this weekend? I’m sorry for the delay on this, it’s been a crazy week for me. I won’t be able to answer everything, as it looks some things are being held back still. But, if you have a few minutes… Let’s take a look at those Hot Chip slides, shall we? 1/34

First of all, a notice: I see a lot of people use my threads and talks for fanboy drivel. If you don’t like what you read, challenge me, talk with me. Don’t instantly move into idiot fanboy mode as you will just get blocked and forgotten. Act your age kids, and discuss. 2/34

Now, for this thread, I’ll only be covering bits and pieces that may be missed or not understood. Some things I’ll leave out, but feel free to ask. First off, let’s put to bed some things: SFS (Extension of SF), VRS and ML, all in. As well as D3D Mesh shading. 3/34

I’ve spoken about SFS and its uses previously, so I won’t go into that here. But VRS being confirmed is a huge win, as is ML acceleration. These are important as it shows a fully-fledged RDNA 2. (At this time of writing, PS5 RDNA status is still up for debate). 4/34

First of all, SOC spec. They appear to be using what they call N7 Enhanced, which is likely a simple custom, more power efficient process over N7P, with a transistor density of 42.5MTr/mm^2. Zen 2. This is likely due to N7+ being more expensive… 5/34

…and serves as a middle ground. For comparison, Playstation 5 uses N7 Zen 2, which is more cost effective, but may come with being less efficient on the whole. Cache allocation seems to be the same as the RX 5700 series, with new ray tracing blocks. 6/34

Here we can see the memory. 10GB @ 560GB/s and 6GB @336GB/s, with 20 channels of x16 GDDR6 @ 14Gbps (560GB/s). For comparison, PS5 has 16GB at 448GB/s. Why the split, and is this good/bad? The split was for cost, I’m sure, but what about the speed difference? 7/34

For what you will need to achieve in a 4k frame buffer 10gb is absolutely fine. I hear people screaming already its low but it really isn’t, not for a console like this. You have 6gb of slower memory as well which is used for OS, but also for less memory intensive tasks. 8/34

What you have to remember is that while PS5 has 16gb (with some reserved for OS), it is ALL at 448GB/s, even though they will use less than 10GB for the stuff that actually needs speed. In short, this memory setup is not only cost effective, but also much better. 9/34

It’s quite well known that the least efficient way to gain performance is by simply increasing the clocks. RDNA doesn’t scale as well at higher clock speeds, and overclocking the RX 5700 XT 18% resulted in just 5-7% improvement. 10/34

However, a 5700XT with 81% more CUs than the 5500XT increases performance 90%+. You always want to be able to do more things simultaneously, even if it means at a slightly slower speed. 11/34

Audio is, as expected, fantastic, and matching in PS5 quality. I don’t know why MS don’t talk about this more, as it’s a heavily marketed feature for PS5, yet we can clearly see there is no slouching going on. 12/34

Of note is that MS also have HRTF support that Sony Tempest engine has. Now, I will go once again on record with this: Don’t expect hundreds of bloody rain drops all in perfect harmony. That’s an absolute waste of time and results in nothing but noise. 13/34

Things like occlusion and reverb will be much better and more enhanced/accurate here and done in hardware instead. We use this in OverDose and it sounds *chefs kiss*. 14/34

Moving on, they state using MSP decompression over 2 general compression blocks, plus a texture compression block, for a total of “OVER” 6GB/s output. Noice. 15/34

Back to GPU, we can see a unified geometry engine, as well as mesh shading geometry engine, plus a 5MB L2 cache (RDNA 1 is 4MB L2). Also unlike RDNA 1, they are using screen tiled colour/depth unit, each consisting of 16 ROPs (RDNA 1 has 4 render backends per array) 16/34

Mesh shading geometry engine - At this time, its currently unknown if it’s used on PS5 via hardware or software. They have been around a while now and are supported on current gen systems, however they come with a hefty performance hit in software. 17/34

Nanite on unreal engine 5 makes heavy use of them, and epic have said “on PS5 they use primitive shaders which are faster than the old vertex shaders”, but this doesn’t fully mean they are 100% supported on PS5, though it would be strange if not IMO. 18/34

It is weird though that even in The Road To PS5, they clearly state they support primitive shaders instead, as the PS5 shades the same as RDNA1… Weird… No idea here, Sony are not being very open, and have stated the contrary, which doesn’t fill me with hope. 19/34

VRS – VRS shows a performance increase of between 10 and 30%, by rendering less pixels in areas of the screen you won’t notice, and is much better than checker board or dynamic resolution, as it maintains clarity. 20/34

At this time, no shown images or information show that PS5 supports VRS. That doesn’t mean it doesn’t support it, it just seems odd that it hasn’t been shown, given it’s quite a decent part of RDNA 2. 21/34

ML – Using ML scaling, series X can increase its performance anywhere from 3 to 10 times, and is shown to support their own version of DLSS (Resolution scaling). A HUGE DEAL, as DLSS is the garlic bread of resolution outputs, i.e. the future. 22/34

RT – ThisIsWhereTheFunBegins .gif In short, it’s good. It’s damn good. For a console, it’s the tits in fact. There was some recent talk about how RT will slow the systems down and developers will have to make a choice, however that was misunderstood. 23/34

What it was actually referring to was that of course RT has a cost in rendering, as does anything, on any system, PS5 and PC no different. But the person in question was merely stating that older traditional methods (SSR, Env/Cube mapping etc) are still there. 24/34

Now, back to the slide. A huge take away here is that it can run in parallel for BVH traversal, material shading etc. This means accurate ray mapping (think light bounces) at a rate of up to 380 billion intersections per second. 25/34

Without dedicated hardware, this would consume over 13tf of power alone, but here is offloaded into dedicated hardware, allowing the shader to run in parallel with no performance loss. This means fantastic RT perf, even if it’s not quite 2080ti level. 26/34

Digital Foundry have also confirmed that developers can access the GPU’s RT units without going through the DirectX API, thus reducing access times and increasing performance. 27/34

This should allow less compromises on RT clarity and accuracy. A massive issue with all PS5 ray tracing seen so far is that it all displays low resolution (quarter res in some cases) with LODs and geo missing in the render. Not terrible, no, but not the best. 28/34

And that about wraps it up for the slides. They showed a lot, but not at the same time. The main take away is that the console will easily and handily be more powerful than the PS5, of course it will. But more importantly it’s not slouching in other areas. VERY balanced. 29/34

As always, comments, chat, questions are welcome. But again, please… Leave the drive by trolling at the door. I don’t care that it’s more powerful than the PS5. I don’t care the PS5 has a better SSD IO. Just chat tech, you tarts. 30/34

Notes:
- There is a dedicated HW decompression block that increases IO throughput.
- Retooled the API with DirectStorage, which increases performance of IO.
- Chipset can emulate FOUR xbox one s systems at once.
- 52 CU setup puts it in the performance range of a 2080.
31/34

- The system is an absolute unit, a cracking piece of hardware.
- It is NOT a basic off the shelf PC. It has a shit load of customisation.
- Of course it’s less exotic as PS5, it has to be. The XSX needs to be closer in ideology to a PC than the PS5 does.
32/34

- With great power comes great… Dollar. It sounds expensive. However, I still expect it to be 500 or lower, and come in cheaper than PS5. That’s just me though, no actual knowledge or anything there.
- Even with all this power, we still have yet to see them use it. SHOW US 33/34

- Thanks to @madzgamingpl for pinching his hot chips slides.
- What the fuck is up with those kellogs blue waffles? I mean… What, you were expecting a better final note?

Thanks for reading! 34/34

@LeviathanGamer2 has also (coincidently I assure you haha!) wrote a more in-depth article along these lines that may be of interest!

Give it a read and give him a follow! 👍🏻

https://twitter.com/leviathangamer2/status/1296956702349197313

Ok... *sigh* once again, lots of decent folk, lots of chatting, DMs; Good stuff. But it’s not even been 12 hours and I have an inbox full of now blocked people, and others antagonising people.

Leave the fanboy stuff at the door!

In two minds ATM about doing this anymore...