Are Graphics Cards superior to CPUs or is it all just smoke and mirrors?

[richaron]

That's the whole concept of DDR, it literally HAS to work in a factor of the base clock, the effective clock rate is actually deceptive, as manufacturers market the effective bandwidth as clock rate, It's NOT clock rate. It's just bandwidth capacity, it should be written like this: 7000MT/s, which means mega transfer per second.

here is how it goes in a very simplistic manner, take an example of a marketed memory speed of 400MHz:

SDR pumps one bit per clock, so base clock is 400MHz, so bus clock is also 400MHz, effective rate is 400MT/s.
DDR pumps two bits per clock, base clock is 200MHz, bus clock should also be 200MHz, effective rate is 400MT/s.
DDR2 pumps four bits per clock, base clock is 100MHz, bus clock is 200MHz, effective rate is also 400MT/s.
DDR3 pumps eight bits per clock, base clock is actually a stunning 50MHz, bus clock is still 200MHz, effective rate is 400MT/s.
DDR5X pumps sixteen bits per clock, base clock is actually an incredible 25MHz, bus clock is still 200MHz, effective rate is 400MT/s.


Do you see what's happening here? SDR had equal base and bus clocks, with equal effective rate (all 400s), however, DDR changed things in a big way, so that for a given speed (400), each generation of DDR effectively halves the base clock of the previous generation, maintains a fixed bus clock of half the effective rate (half the 400 is 200). Thus each generation saves power, voltage and durability for exactly the same effective rate of 400MT/s in my example.

DDR ≠ GDDR

 

[lakedude]

The question is weather a CPU or dGPU is "better".

If we are talking about an APU the answer has already been given. A good dedicated card is going to be faster but it will use more electrical power. An APU could be a good thing in a power restricted environment like a laptop or if you just don't need better graphics. A modern APU is plenty for non-gaming day to day use. For the foreseeable future a dGPU is going to be better in a desktop with a big power budget.

At some point it looked like the OP literally intended to compare a non-APU CPU to a GPU. These devices are not really directly comparable. A modern multi core CPU is a fast general purpose device that can do a few things at a time, like a work crew of a few smart handymen. They can do anything from flooring to roofing and they are each really fast. If they need to do something new they will figure it out and get it done. Putting up a roof might take them all day but they can do such a job. When a CPU proper (not an APU) is asked to render video it is call "software rendering".

A GPU is less flexible and would be more like a couple thousand slower dudes who only know how to shingle roofs and who don't speak English. If you need new carpet these are not the guys you call, they can't do this job at all and they never will be able to. If you need a new roof put on in seconds these guys can handle the job.

A GPU's speed comes more from massive parallelism and a more specific workload with specifically tailored hardware while a CPU's speed comes more from a higher clock.

Check out this picture (I remember this like yesterday as it cemented what a video card was in my mind):

Notice that the software render on the left has fewer colors and lower resolution. The picture shows them both at 30FPS but I can assure you that GL Quake was much much smoother on a 3dfx card than the choppy, pixelated, slide show that was the software render.

Now we have come a long way and a modern CPU would do a better job but the principle is the same. We have a lot more pixels to push (shingle) these days with 1080p or 4k monitors.

 

[TestKing123]

The question is weather a CPU or dGPU is "better".

If we are talking about an APU the answer has already been given. A good dedicated card is going to be faster but it will use more electrical power. An APU could be a good thing in a power restricted environment like a laptop or if you just don't need better graphics. A modern APU is plenty for non-gaming day to day use. For the foreseeable future a dGPU is going to be better in a desktop with a big power budget.

At some point it looked like the OP literally intended to compare a non-APU CPU to a GPU. These devices are not really directly comparable. A modern multi core CPU is a fast general purpose device that can do a few things at a time, like a work crew of a few smart handymen. They can do anything from flooring to roofing and they are each really fast. If they need to do something new they will figure it out and get it done. Putting up a roof might take them all day but they can do such a job. When a CPU proper (not an APU) is asked to render video it is call "software rendering".

A GPU is less flexible and would be more like a couple thousand slower dudes who only know how to shingle roofs and who don't speak English. If you need new carpet these are not the guys you call, they can't do this job at all and they never will be able to. If you need a new roof put on in seconds these guys can handle the job.

A GPU's speed comes more from massive parallelism and a more specific workload with specifically tailored hardware while a CPU's speed comes more from a higher clock.

Check out this picture (I remember this like yesterday as it cemented what a video card was in my mind):

Notice that the software render on the left has fewer colors and lower resolution. The picture shows them both at 30FPS but I can assure you that GL Quake was much much smoother on a 3dfx card than the choppy, pixelated, slide show that was the software render.

Now we have come a long way and a modern CPU would do a better job but the principle is the same. We have a lot more pixels to push (shingle) these days with 1080p or 4k monitors.

You don't even have to go that far. And it's not quite comparable because the software renderers of old didn't render exactly the same image as a dedicated 3D accelerator, they took shortcuts which is why they looked pixelated and ugly.


For a direct comparison, just take an OpenGL game, even Doom 4, and run it in OpenGL software mode. Let me know how many minutes it takes the CPU to draw just 1 frame.

 

[lakedude]

For a direct comparison, just take an OpenGL game, even Doom 4, and run it in OpenGL software mode. Let me know how many minutes it takes the CPU to draw just 1 frame.

I will! Thanks for making this an apples to apples comparison and bringing us into this century...

 

[Charlie22911]

I'd be curious to know the usefulness of software rendering as a benchmarking tool, and also how performance scales with cores. Intuition tells me it should scale linearly with core count, but in practice I'm sure some other bottleneck will prove me wrong.

 

[whm1974]

I'd be curious to know the usefulness of software rendering as a benchmarking tool, and also how performance scales with cores. Intuition tells me it should scale linearly with core count, but in practice I'm sure some other bottleneck will prove me wrong.

Lack of bandwidth in comparison with dGPUs is the first bottleneck that comes to mind.

 

[lakedude]

My guess is that your original assumption is correct. They say rendering is "embarrassingly parallel" so it would scale with core count.

 

[lakedude]

Lack of bandwidth in comparison with dGPUs is the first bottleneck that comes to mind.

I ain't no expert on this stuff but I'm guessing the reason a dGPU needs so much bandwidth is because of how massively parallel a graphics card is. You are feeding a lot of hungry workers!

A CPU, even a high core count CPU is much much less parallel and therefore I suspect does not need anywhere near the bandwidth. The workers may each be more hungry but there are far, far fewer mouths to feed.

 

[TheDarkKnight]

The question is weather a CPU or dGPU is "better".
At some point it looked like the OP literally intended to compare a non-APU CPU to a GPU.

My intention was never to compare a non-APU to a dGPU. The first sentence in my post gives "some clues" as to context. "I just bought an AMD 2200G".

Well, honestly, what I was asking was more along the lines of 'which is the superior device or solution' (and of course, this has to be a subjective opinion at the end of the day I guess) in terms of how the solution is implemented. It's pretty difficult for me to put my question into words. I guess what I was asking (but I'm thinking to myself and I'm saying right now) is that I'm very highly impressed (I bought their new APU...afterall) by the fact that AMD has released an APU with RX 550 performance in a 65-watt power envelope for $99.00. That blows my mind considering that an RX550 discrete graphics card can cost that much alone. But you hear gamers going around complaining and saying things like, "Nope, not there yet!!!" Yeah, okay, not there yet. Because AMD is NOT using 200 watts of power for their APU, AMD's NOT using GDDR5 memory, AMD is NOT using a 256-bit memory bus (like some graphics cards do), AMD's APU is NOT using a million CU's or MP's or whatever you call them. In other words (for the people who missed my point) I think AMD's APU's are superior in their designs for what they offer. I'm not saying by any stretch of the imagination that they are anywhere near being "as fast" as a discrete GPU. It's as one of the previous posters said. Something along the lines of, "A discrete GPU is like having 10000 roofers all doing the same job because it's all they know, they know it well, and they do it fast. But they can't speak English".
.
So, my question was legit. I'm glad I posted it. There was some incredible knowledgeable responses to this thread and I think I ended up "liking" half of them. I'll have to read these again when I have more sleep.

EDIT: So, as I think about this and comments like, "Nope, not their yet." Does that kind of a comment make any sense? Do humans EVER stop wanting more power? No. So, my point, and I think somebody said this in the thread also, is that AMD "could" make an APU as powerful as a discrete GPU. In a sense they already have, it's called a game console.Maybe the game console is technologically superior to both APUs and dGPUs? Maybe it's the best of both worlds.

 

[lakedude]

My intention was never to compare a non-APU to a dGPU.

Sorry, my mistake. Your wording had several of us a little confused. I always thought your question was "legit".

Your logic behind your purchase is sound. You are correct that at that price your chip can't be beat. AMD is basically charging you for a CPU and giving you a decent GPU for free.

 

[lakedude]

For a direct comparison, just take an OpenGL game, even Doom 4, and run it in OpenGL software mode.

How do you do this? I've got Open GL 4.5 and Vulcan as my choices.

 

[whm1974]

Sorry, my mistake. Your wording had several of us a little confused. I always thought your question was "legit".

Your logic behind your purchase is sound. You are correct that at that price your chip can't be beat. AMD is basically charging you for a CPU and giving you a decent GPU for free.

I agree that the OP purchase is sound for what is he doing with it, although I don't know if I would call Rx550/1030 level GPU decent, but for what it is then yes.

 

[2is]

EDIT: So, as I think about this and comments like, "Nope, not their yet." Does that kind of a comment make any sense? Do humans EVER stop wanting more power? No. So, my point, and I think somebody said this in the thread also, is that AMD "could" make an APU as powerful as a discrete GPU. In a sense they already have, it's called a game console.Maybe the game console is technologically superior to both APUs and dGPUs? Maybe it's the best of both worlds.

Consoles have neither the best graphics processing nor do they have the best CPU. Your definition of "best" is what the rest of the world actually calls a "compromise" because that's exactly what you get. A compromise between CPU/GPU processing with a reasonable power envelope for a reasonable price. If you game with a controller exclusively there's no reason not to get one if you're looking for "bang for buck" gaming.

Probably the one area where you can say consoles are the "best" at isn't at the hardware level, but the software optimization. Your GHz go a lot further when developers are just coding for a very specific set of hardware.

 

[Denithor]

Sorry, my mistake. Your wording had several of us a little confused. I always thought your question was "legit".

Your logic behind your purchase is sound. You are correct that at that price your chip can't be beat. AMD is basically charging you for a CPU and giving you a decent GPU for free.

So, here's the rub in all this. Yes, you're getting the equivalent of a "decent" GPU essentially free with your CPU purchase. However, that "decent" GPU is only equivalent to the very bottom end of what's available in the dGPU world. Although, depending on your particular uses, it may be completely satisfactory, for (probably) the majority of "gamers" out there, it simply doesn't have the power to push the frame rates and resolutions desired.

Note, I'm not knocking your decision or perception at all, simply pointing out that many/most serious gamers want/need more powerful GPU than what an APU can provide today. APUs have come a long way in a few years but they continue to simply nip at the very lowest edge of what the dGPUs can provide. And this is likely to continue, for exactly the reason pointed out above: case design/layout is not adequate to cool a 200+ watt APU (would actually need to be 300+W total to match today's higher end cards + CPU).

Also, this only really applies to GAMERS. General users get more than enough power out of these APUs for watching movies and most other simple rendering requirements. And today's APUs are worlds better than we had like ten years ago, when an "integrated" GPU was built into the motherboard instead of included in the CPU. Those options were, quite simply, horrible.

 

[Jaskalas]

I've recently purchased an AMD 2200G CPU...
...
So, I was looking at buying a discrete RX 560...

Others appear to have answered the technical and practical reasons why a GPU is faster. Now I'll demonstrate just how much faster. And yes, this is really all for the purpose of pushing frame rates in games.

RX Vega 8 VS:
RX 560: 99% faster.
GTX 1050-Ti: 148% faster.
RX 570: 278% faster.
GTX 1060 6GB: 357% faster.
etc...

 

[Blitzvogel]

EDIT: Maybe the game console is technologically superior to both APUs and dGPUs? Maybe it's the best of both worlds.

The original PS4 and Xbone SoCs are based on 2013 technology, and that limiting factor did carry over to the PS4 Pro and XBX SoCs since they are still using Jaguar cores. Yeah they've gotten clock bumps and may even benefit from architectural improvements found in Puma (no confirmation of this), but they are still rather limited compared to any modern big core. Hell, they were limited in 2013, and even compared to the previous consoles, they were in some ways barely better.

Sure the PS4 put a premium on GPGPU with extra ACEs, PS4Pro is a Vega/Polaris hybrid (a year before Vega), and XBX simply has a massive APU, but any possible feature set advantages are exceeded by sheer brute force on PC. It hasn't been since the launch of the Xbox 360 had a console enjoyed a clear advantage over PC in that both feature set and gaming related processing power. But it only took a year for it to get BTFO'd by the combination of an 8800 GTX and a Core 2 Quad.

 

[lakedude]

The purchase of a Ryzen 3 2200G alone makes a lot more sense than the purchase of a Ryzen 3 1200 (at nearly the same price) with a GTX 1030 or similar dGPU. The 2200G is the "superior"deal by a large margin.

OMG I just saw that they are claiming the 2200G is "VR ready". I'm not so sure about that.

 

[Guru]

The purchase of a Ryzen 3 2200G alone makes a lot more sense than the purchase of a Ryzen 3 1200 (at nearly the same price) with a GTX 1030 or similar dGPU. The 2200G is the "superior"deal by a large margin.

OMG I just saw that they are claiming the 2200G is "VR ready". I'm not so sure about that.

Overall its cheaper than buying a standalone CPU and DGPU, but a dedicated dgpu like the GT 1030 is still faster than Vega 8 in the 2400g. In fact its about 35% faster on average over the 2400G and over 40% faster than the 2200G.

 

[lakedude]

Overall its cheaper than buying a standalone CPU and DGPU, but a dedicated dgpu like the GT 1030 is still faster than Vega 8 in the 2400g. In fact its about 35% faster on average over the 2400G and over 40% faster than the 2200G.

Assuming budget is a factor which would you buy? For a nice everyday system I'd buy the 2200G over the 1200 every time.

 

[Yuriman]

I don't believe this was brought up, but having a GPU on a socketed CPU using socketed RAM has some major disadvantages. There isn't much inherent in the design of a GPU sharing a die with a CPU that makes it better or worse than one alone, but how it's packaged can make a huge difference.

Ever wonder why socketed CPUs and iGPUs don't have GDDR5? To my understanding, it's signaling limitations. You would need to integrate the RAM into the motherboard immediately around the socket, much like it's done on a GPU. You may also even need to solder the CPU package to the board to make this possible.

With those hard memory bandwidth constraints in place, you can only make an iGPU so big before performance stops increasing.

 

[wahdangun]

Yeah, I remember when the first APU was released years ago, and there was similar talk on these forums and many others about how the APU was eventually going to replace the dGPU by virtue of everything being on the same die. I scoffed at it back then, and I still scoff at it right now.

The only thing APUs will be better at is performance per watt. For raw performance though, nothing beats discrete parts.

APU in Xbox one x is faster than Rx 580 and approaching 1070.

So yes APU can actually replace dgpu, if AMD wanted.

Maybe next year with the leak of fenghuang APU, 28 cu and 2/4 GB hbm.

 

[wahdangun]

If you want to make an APU as powerful as a a discrete GPU, you need to give it a power budget as big as a discrete GPU. There's a reason why the PS4, PS4 Pro and XBox One X have heatsinks that look a lot like a GPU cooler, with a big blower fan pushing air through the fins:

Sadly, the standard PC ATX design is complete garbage, and not designed for this style of high performance coolers. It's a 20+ year old design built around 35W CPUs from the 90s, with their dinky little heatsinks and low airflow requirements. It's completely atrocious at getting cold air to the CPU socket, and then exhausting hot air out the back of the case. Instead everything sits in a warm soup, with hot air swirling around inside the case. That's why people have resorted to insane hacks like watercooling, with radiators bolted onto the side of the case so they can actually access some fresh cold air to cool their CPU.

If you really want high performance APUs, you either need a fully custom case design (like the consoles), or you need the industry to ditch ATX/uATX/mITX and move to a replacement that specifies a much better socket layout and airflow. Otherwise you'll be limited to ~95W for the entire CPU & GPU combined.

No it's not limited to 95 watt, just look at TR it can reach 180 watt. So atx specifications not limited to 95 watt. It's just the market and amd starved for RnD.

Overall its cheaper than buying a standalone CPU and DGPU, but a dedicated dgpu like the GT 1030 is still faster than Vega 8 in the 2400g. In fact its about 35% faster on average over the 2400G and over 40% faster than the 2200G.

No 2400g have Vega 11and it's faster than 1030, and can even be much faster if you oc'd to 1600 mghz.

 

[whm1974]

APU in Xbox one x is faster than Rx 580 and approaching 1070.

So yes APU can actually replace dgpu, if AMD wanted.

Maybe next year with the leak of fenghuang APU, 28 cu and 2/4 GB hbm.

I doubt this is the case at all. Can show us where you gotten these figures?

 

[wahdangun]

I doubt this is the case at all. Can show us where you gotten these figures?

It's in sisoftsandra database leak. It's all over the net.

https://www.tweaktown.com/news/6015..._comment_id=1586392681400026_1586484084724219

Pretty much Rx 570D performance in APU package.

 

[whm1974]

It's in sisoftsandra database leak. It's all over the net.

https://www.tweaktown.com/news/6015..._comment_id=1586392681400026_1586484084724219

Pretty much Rx 570D performance in APU package.

Actually it say it should more powerful then the Vega 8 and 10(Meant 11?) iGPUs which at best matchs the GeForce 1030 GPU. So maybe a 1050 with 2GB of Video Memory? Yawn!!!