Investigation Shows That NVIDIA GPUs Implement Tile Based Rasterization for Greater Efficiency

[DocSwag]

4 minutes ago, Prysin said:

THat would explain why Nvidia GPUs get different lightning signatures in Ashes of the Singularity then AMD based cards. Their "tweaking" simply doesnt work and or doesnt fit with the way the game is built.

Oh my god! Everything we've seen so far is making so much sense now!

[DocSwag]

2 minutes ago, Prysin said:

AMD introduced a similar system with Polaris. It is one of the Rasterization optimizations that came with GCN4

Are you talking about the primitive discard accelerator?

 

That is somewhat similar, though it seems to approach the problem from a different angle. Also I'm not sure if the PDA discards triangles behind opaque objects... As far as I know it only discards super tiny ones though correct me if I'm wrong.

[Nineshadow]

1 hour ago, Master Disaster said:

If so then I'd agree it's not a bad thing as long as it is more efficient but I'd question that fact, rendering 36 small frames compared to just 1 big one must equal the same amount of overall work done so is the efficiency gains due to multithreading and simultaneous processing? 

Think about it like Divide et Impera (divide and conquer).

[Zodiark1593]

Does the GPU render the frame in the large L2 cache,  or does it only contain the resources needed to render the frame? 

 

This could explain why the 960 and 970 are penalized so heavily in particular, as they've only 1MB and 1.5MB of L2 cache respectively. 

 

[Nineshadow]

5 minutes ago, Zodiark1593 said:

Does the GPU render the frame in the large L2 cache,  or does it only contain the resources needed to render the frame? 

 

This could explain why the 960 and 970 are penalized so heavily in particular, as they've only 1MB and 1.5MB of L2 cache respectively. 

 

Yeah, I think it renders it in the L2 cache. It would make the most sense tbh.

[That Norwegian Guy]

I wonder if this is responsible for the crushed blacks my brother is getting on his Maxwell card in gaming where my 290x renders a better image. Very noticeable in some games like the Batman series, Styx and other dark games.

[Zodiark1593]

2 hours ago, That Norwegian Guy said:

I wonder if this is responsible for the crushed blacks my brother is getting on his Maxwell card in gaming where my 290x renders a better image. Very noticeable in some games like the Batman series, Styx and other dark games.

I wouldn't think color would be much affected unless the game engine was doing weird stuff where rendering the entirety of the image at once was a requirement. (in some cases, drivers could substitute in shaders and other such code to approximate effects for their hardware if there was something really broken or slow). 

 

I'd look toward the monitor differences before the video card though as far as color differences go. 

[That Norwegian Guy]

6 minutes ago, Zodiark1593 said:

I wouldn't think color would be much affected unless the game engine was doing weird stuff where rendering the entirety of the image at once was a requirement. (in some cases, drivers could substitute in shaders and other such code to approximate effects for their hardware if there was something really broken or slow). 

 

I'd look toward the monitor differences before the video card though as far as color differences go. 

Both are 8-bit panels with 10-bit lookup tables so that possibility is already dismissed. Has to be GPU (he has no image/ colour altering in Nvidia control panel, nor do I, and we're both on the same OS)

 

Also he didn't have this problem with his GTX 760.

[Dabombinable]

7 minutes ago, Zodiark1593 said:

I wouldn't think color would be much affected unless the game engine was doing weird stuff where rendering the entirety of the image at once was a requirement. (in some cases, drivers could substitute in shaders and other such code to approximate effects for their hardware if there was something really broken or slow). 

 

I'd look toward the monitor differences before the video card though as far as color differences go. 

Especially with IPS vs TN panels. Despite the lower resolution for example on my Transformer Prime TF201, its IPS display looks far better than my desktops 1080p TN display (and infact so does the display on my U38N-1080p IPS that's better again than the Prime's-)

[laminutederire]

Nvidia is using a trick to do less calculation, if others don't do it there is a possibility that it could affect the final rendering. 

Now we know why nvidia is no better at power efficiency than amd but still manage to do better : they are more computing efficient apparently.

[Valentyn]

5 hours ago, That Norwegian Guy said:

I wonder if this is responsible for the crushed blacks my brother is getting on his Maxwell card in gaming where my 290x renders a better image. Very noticeable in some games like the Batman series, Styx and other dark games.

I honestly recently noticed something similar.

Between my 980Ti and 390X, the latter had better colour reproduction in games that had a very detailed colour palette; such as WoW.
 

Got to the point I had to call in a friend and force them to sit around as I reinstalled the different cards, drivers and all to see if I wasn't imagining things. The 390X just had better colour reproduction and details in that game for me, and in DOOM.

[Prysin]

3 hours ago, Dabombinable said:

Especially with IPS vs TN panels. Despite the lower resolution for example on my Transformer Prime TF201, its IPS display looks far better than my desktops 1080p TN display (and infact so does the display on my U38N-1080p IPS that's better again than the Prime's-)

TN is so shit. I recently visit a different LTT member to help mod a case and build a monitor stand. He had some TN panels and i was totally "triggered" from how bad TN is... its been 6 years since my last TN panel and i plan to not buy another one.

 

VA or IPS or OLED/AMOLED.

[Dabombinable]

5 minutes ago, Prysin said:

TN is so shit. I recently visit a different LTT member to help mod a case and build a monitor stand. He had some TN panels and i was totally "triggered" from how bad TN is... its been 6 years since my last TN panel and i plan to not buy another one.

 

VA or IPS or OLED/AMOLED.

For me it was getting something better than my old LCD monitor for cheap-and I could only afford this screen. My LCD monitor actually had the viewing angles of a TN panel, the colour quality of an IPS panel, and an 85Hz refresh rate. Some days I really miss it-especially when watching movies. But that's the price of getting a modern 1080p LCD screen for cheap instead of using one from 2002-2004 that was designed to compete with CRT monitors in all areas.

[Prysin]

4 minutes ago, Dabombinable said:

For me it was getting something better than my old LCD monitor for cheap-and I could only afford this screen. My LCD monitor actually had the viewing angles of a TN panel, the colour quality of an IPS panel, and an 85Hz refresh rate. Some days I really miss it-especially when watching movies. But that's the price of getting a modern 1080p LCD screen for cheap instead of using one from 2002-2004 that was designed to compete with CRT monitors in all areas.

you should look at VA vs IPS. It is amazing when you talk about contrasts. Colors however is flat out IPS. Except AMOLED/OLED...

 

My Samsung tablets screen is fucking "panel porn"... so retardedly beautiful to watch and so fucking bright.

[ManIkWeet]

It's really interesting to watch the video, I recommend doing so.

 

He explains very clearly how this new method of rasterizing works!

 

TLDW: NVidia splits the work in small parts, small parts fit in tiny faster memory, less time wasted by accessing large slow memory.

[Dabombinable]

12 minutes ago, Prysin said:

you should look at VA vs IPS. It is amazing when you talk about contrasts. Colors however is flat out IPS. Except AMOLED/OLED...

 

My Samsung tablets screen is fucking "panel porn"... so retardedly beautiful to watch and so fucking bright.

Honestly, nothing matches the old CRT in contrast, colours or view angles-but after using a Transformer Prime TF201 and Asus U38N (the "high end" model), screw getting TN panels (especially if they are 27" and are only 1080p-I can actually see the pixels easily from half a meter away).

 

Edit: BTW, the Prime has the "Super IPS" mode, and it makes the image quality even better-of course being a lot brighter than normal, it drains the battery extremely fast (even when plugged into its dock).

[Nineshadow]

15 hours ago, patrickjp93 said:

Deduplication of lighting work. Stamp the same lighting signature across the similar tiles and then tweak as needed. It's the same with tiled texturing.

Really? From my knowledge, tile based rendering is just that...splitting the workload into smaller ones; divide and conquer. On the plus side, if the workload is split into small enough packets to fit the cache, then that would make things quite faster.

[laminutederire]

1 hour ago, Valentyn said:

I honestly recently noticed something similar.

Between my 980Ti and 390X, the latter had better colour reproduction in games that had a very detailed colour palette; such as WoW.
 

Got to the point I had to call in a friend and force them to sit around as I reinstalled the different cards, drivers and all to see if I wasn't imagining things. The 390X just had better colour reproduction and details in that game for me, and in DOOM.

Could you send screenshots so that we can see as well?

[Valentyn]

7 minutes ago, laminutederire said:

Could you send screenshots so that we can see as well?

Sold my 980Ti's to said friend and 390X is gone as well; although I would have needed to take a photo to get a very accurate image of it. I'm currently on a little 6670, waiting to see how well the new TX performs before pulling the trigger on a new GPU.

The other thing I saw after looking into it a bit more; well especially in regards to DOOM is that NVIDIA cards load the textures in slower than AMD ones.

The 1080 is much better at it than Kepler and Maxwell cards, but is still a smidge slower than even the RX 480. 
Depends on the person on how much they notice it; but it's most likely due to texture compression and streaming tech there.

 

[patrickjp93]

1 hour ago, Nineshadow said:

Really? From my knowledge, tile based rendering is just that...splitting the workload into smaller ones; divide and conquer. On the plus side, if the workload is split into small enough packets to fit the cache, then that would make things quite faster.

It does both, but the asymptotic runtime is hugely reduced under the tiling model, and it's significantly more important that we went from an N^2 algorithm to an n*lg(n) algorithm.

[laminutederire]

34 minutes ago, Valentyn said:

 

Also if they put in smaller caches that could explain why, because they'd have to compute who goes where since caches are tinier.

That could explain some part of the fps gap for same Tera flops cards. If they used lower resolution textures for small amounts of time, nearly all the time, at the end of the day that could amount to a significant framerate improvement.

[Zodiark1593]

15 hours ago, Nineshadow said:

Really? From my knowledge, tile based rendering is just that...splitting the workload into smaller ones; divide and conquer. On the plus side, if the workload is split into small enough packets to fit the cache, then that would make things quite faster.

The idea behind tiled rendering is rendering to a tiny buffer on cache is eons faster than manipulating the image in VRAM. This is why this technique is so common in mobile where bandwidth is a (very)  sparse resource. There is a performance overhead though, due to the tiling and switching between tiles, though with a smaller bandwidth, the performance boost can outweigh that overhead. 

 

If buffer/memory size/bandwidth is not a factor, then Immediate Mode should be faster. 

[AlTech]

It's good to see Nvidia supporting Direct X 11.1 and 11.2 even though only people on Windows 8 or above will be able to use the feature.

[vanished]

6 minutes ago, AluminiumTech said:

It's good to see Nvidia supporting Direct X 11.1 and 11.2 even though only people on Windows 8 or above will be able to use the feature.

Well consider the alternative: they choose to not support it and basically say "This is the end of the line.  We will not be making any future products or updating for modern technology"  

[AlTech]

Just now, Ryan_Vickers said:

Well consider the alternative: they choose to not support it and basically say "This is the end of the line.  We will not be making any future products or updating for modern technology"  

The market share of Windows 8 and above is over 20%. Not the majority.

 

And thus most people would never care so why do it? Many people on the forum seem to want to stay with Windows 7 forever because it's "perfect".