16GB vram enough for the 6900XT? Discuss..

[Nablaoperator]

That is the problem though, you cannot use more video memory than what your card has so it makes this metric kind of pointless. You could require 16GB but your actual usage will not go over 8192MB, as that's all your GPU has so its not really showing you the video memory required to ensure an optimal experience. In the screenshot it shows allocated at 8GB and actual usage at 6.8GB right?

You are basically running 4K with 2x super sampling on the resolution(so probably 8K or something) the video memory usage requirements for that with a HQ Texture pack are huge, yet somehow you can manage that while only using 6.8GB of video memory?

One possible way to validate that would be to look at bandwidth utilisation.
Memory channels on your card should be relatively free compared to frosty's. is there a way to acquire that data?

 

[LtMatt]

One possible way to validate that would be to look at bandwidth utilisation.
Memory channels on your card should be relatively free compared to frosty's. is there a way to acquire that data?

Probably.

I just tested 5120x1440 with 200% resolution scaling. Memory usage started off at 10GB as soon as i spawned into the region. Got into a car and it had hit 11.3GB actual usage. That's before even driving anywhere. I disabled HDR this time, but i am not sure if having that enabled in all my testing previously caused an increased in video memory usage, this is another variable we probably have not accounted for.

Spoiler

 

[Nablaoperator]

I don't know the exact tech details..
Do the controllers for acquiring data on VRAM reside in the card or is data pushed into PCI lanes by the CPU/chipset?

Either way it would be interesting to see if there's some kind of saturation numbers related to VRAM data acquisition

 

[PrincessFrosty]

That is the problem though, you cannot use more video memory than what your card has so it makes this metric kind of pointless. You could require 16GB but your actual usage will not go over 8192MB, as that's all your GPU has so its not really showing you the video memory required to ensure an optimal experience. In the screenshot it shows allocated at 8GB and actual usage at 6.8GB right?

You are basically running 4K with 2x super sampling on the resolution(so probably 8K or something) the video memory usage requirements for that with a HQ Texture pack are huge, yet somehow you can manage that while only using 6.8GB of video memory?

The memory allocated typically will not go above the amount of vRAM on the card (although it could if you wrote your game engine to allocate that much, the video drivers would just assign some space on disk to page memory off to), but most modern game engines will never request allocation above the vRAM size because disk access when assets are paged there is very bad, it can't be used for anything real time.

The amount "used" in this case the total dedicated memory for the farcry5.exe process can never be more than what the engine has allocated itself from the GPU. In my screenshot the amount used is only 6799Mb which is about right.

You're right about 8k, the game is just rendering a 2x the resolution which is 8k total and then downsampling to provide essentially SSAA to the whole scene. But your expectations are way off, is what I'm saying. The memory requirements of a 4k frame buffer are only about 53Mb in vRAM, and 8k frame buffer use is about 256Mb of vRAM. Any other graphical effect that needs more memory per pixel will also need more vRAM and thats what you see a healthy jump from about 5800Mb of usage to 6800Mb. The problem with 8k gaming isn't really vRAM at all it's the GPU speed needed to process 33 million pixels per frame.

That is 4k Ultra with the HD texture pack on, I dunno what to tell you...

My control panel on youtube is telling me that HD processing is now done although it's not an option yet on the video playback, but it should appear shortly https://www.youtube.com/watch?v=r3DA2b3lw1A

That's recorded with Nvidia Geforce experience video capture set to record at native res (4k) and the high quality preset which puts the bitrate to 50Mbps.

 

[LtMatt]

The memory allocated typically will not go above the amount of vRAM on the card (although it could if you wrote your game engine to allocate that much, the video drivers would just assign some space on disk to page memory off to), but most modern game engines will never request allocation above the vRAM size because disk access when assets are paged there is very bad, it can't be used for anything real time.

The amount "used" in this case the total dedicated memory for the farcry5.exe process can never be more than what the engine has allocated itself from the GPU. In my screenshot the amount used is only 6799Mb which is about right.

You're right about 8k, the game is just rendering a 2x the resolution which is 8 total and then downsampling to provide essentially SSAA to the whole scene. But your expectations are way off, is what I'm saying. The memory requirements of a 4k frame buffer are only about 53Mb in RAM, and 8k frame buffer use is about 256Mb of vRAM. Any other graphical effect that needs more memory per pixel will also need more vRAM and thats what you see a healthy jump from about 5800Mb of usage to 6800Mb. The problem with 8k gaming isn't really vRAM at all it's the GPU speed needed to process 33 million pixels per frame.

That is 4k Ultra with the HD texture pack on, I dunno what to tell you...

My control panel on youtube is telling me that HD processing is now done although it's not an option yet on the video playback, but it should appear shortly https://www.youtube.com/watch?v=r3DA2b3lw1A

That's recorded with Nvidia Geforce experience video capture set to record at native res (4k) and the high quality preset which puts the bitrate to 50Mbps.

Agreed, which makes this metric pointless for testing required video memory. It's okay you don't need to tell me anything as you've not changed my opinion on this on based on what you have presented to me. And that's okay, it's nice to have a civil debate.

I do appreciate the effort you took to record the video and the tool you shared. Unfortunately the testing you used is not the same as what i tested (driving from region to region which i found to show this issue) and the video did not display frame time graph data (which is possible using MSI Afterburner) which would show any hitching you see in game due to a lack of video memory by displaying the time it takes to render a frame. A spike in frame time would indicate a hitch in this example and was what i used to test the video memory requirements. A hitch would occur on an 8GB card whereas it would not on a 16GB card. This appears to be a decent way to test video memory usage requirements with the current tools we have.

 

[Nablaoperator]

A hitch would occur on an 8GB card whereas it would not on a 16GB card.

That's what I believe would be the case as well with this new data coming in..
GPU missing a hit on VRAM will be extremely expensive.
But it could also mean that the memory manager is not aggressively purging data because more of it is available

 

[LtMatt]

That's what I believe would be the case as well with this new data coming in..
GPU missing a hit on VRAM will be extremely expensive.
But it could also mean that the memory manager is not aggressively purging data because more of it is available

Yeah as we can see it's difficult to test this. Maybe I'm wrong, can't say with 100% certainty I'm right but i can't see any other reason why i saw that behaviour, and i only saw it on games with high video memory utilisation. Most games, where usage was below 8GB (that's 8GB total system video memory usage not just the game) showed no issue at all.

 

[PrincessFrosty]

Agreed, which makes this metric pointless for testing required video memory. It's okay you don't need to tell me anything as you've not changed my opinion on this on based on what you have presented to me. And that's okay, it's nice to have a civil debate.

I do appreciate the effort you took to record the video and the tool you shared. Unfortunately the testing you used is not the same as what i tested (driving from region to region which i found to show this issue) and the video did not display frame time graph data (which is possible using MSI Afterburner) which would show any hitching you see in game due to a lack of video memory by displaying the time it takes to render a frame. A spike in frame time would indicate a hitch in this example and was what i used to test the video memory requirements. A hitch would occur on an 8GB card whereas it would not on a 16GB card. This appears to be a decent way to test video memory usage requirements with the current tools we have.

Huh? No it's not pointless, it's telling you what the game is genuinely using on your hardware. The Memory allocated is the useless number because that process can be allocated way more memory than it actually uses.

The likely difference in our memory usage is probably due to how the game engine flushes unused assets from memory, like with most of these open world games the amount of assets in the game is extremely high, way higher than 8Gb of vRAM and way higher than 16Gb on the Radeon VII, and even way higher than 24Gb of the 3090, the game install folder for me on steam with the HD textures installed is 67,895 MB and textures are stored compressed on disk and when uncompressed into vRAM are much larger with their extracted mipmaps and all that, so it's probably more like 100Gb of raw uncompressed game data. It seems likely that if you're getting any hitching its when the internal memory pool for the engine is getting full and flushes old data it doesn't need to make room for. if that's the case you'll get hitching on a 16Gb card too it just wont happen as fast. But you're not putting the entire games asset budget into 16Ggb lol.

I mean do we have anyone with a 3090 reading this thread? Can we just drive around with a 24Gb card until that fills up to like 20Gb of used memory and then proclaim that a 16Gb card is not enough? That's obviously not a good way of measuring vRAM requirements, if the engine isn't purging unused assets until the vRAM is close to running out.

I'll re-test with frame time on, on the ground in a vehicle driving between zones and record it again. Although the 1080s GPU is slower so my frame rate is lower so my frame times are going to be higher, i wouldn't normally play on all ultra with a single 1080 because the 40-50fps isn't really high enough for my liking, I only maxed it out in this case to put the most strain possible on the vRAM at 4k.

 

[LtMatt]

Huh? No it's not pointless, it's telling you what the game is genuinely using on your hardware. The Memory allocated is the useless number because that process can be allocated way more memory than it actually uses.

The likely difference in our memory usage is probably due to how the game engine flushes unused assets from memory, like with most of these open world games the amount of assets in the game is extremely high, way higher than 8Gb of vRAM and way higher than 16Gb on the Radeon VII, and even way higher than 24Gb of the 3090, the game install folder for me on steam with the HD textures installed is 67,895 MB and textures are stored compressed on disk and when uncompressed into vRAM are much larger with their extracted mipmaps and all that, so it's probably more like 100Gb of raw uncompressed game data. It seems likely that if you're getting any hitching its when the internal memory pool for the engine is getting full and flushes old data it doesn't need to make room for. if that's the case you'll get hitching on a 16Gb card too it just wont happen as fast. But you're not putting the entire games asset budget into 16Ggb lol.

I mean do we have anyone with a 3090 reading this thread? Can we just drive around with a 24Gb card until that fills up to like 20Gb of used memory and then proclaim that a 16Gb card is not enough? That's obviously not a good way of measuring vRAM requirements, if the engine isn't purging unused assets until the vRAM is close to running out.

I'll re-test with frame time on, on the ground in a vehicle driving between zones and record it again. Although the 1080s GPU is slower so my frame rate is lower so my frame times are going to be higher, i wouldn't normally play on all ultra with a single 1080 because the 40-50fps isn't really high enough for my liking, I only maxed it out in this case to put the most strain possible on the vRAM at 4k.

If you can show me a screenshot of the actual used video memory, in any game of your choice, exceeding the amount of available video memory on your GPU, then the metric will have some value in showing the video memory required to run the game optimally. If you could have done this, i am sure you would have by now though.

I think we'll just have to agree to disagree, unfortunately you have not managed to convince me this time based on my personal testing with two different GPUs.

As long as the frame time graphs do not show any spikes, it won't matter if your FPS are 45 or 95 as long as they are consistent. Here is a video showing you how to setup the frame time graphs. https://www.youtube.com/watch?v=8Kskk5tEBx8

EDIT

I clearly explained Frosty how i tested this with an 8GB GPU and a 16GB GPU. If you do not believe me that's okay, but i am surprised that you said this.

I mean do we have anyone with a 3090 reading this thread? Can we just drive around with a 24Gb card until that fills up to like 20Gb of used memory and then proclaim that a 16Gb card is not enough?

I think that is me bowing out now, i wish you all the best.

 

[PrincessFrosty]

If you can show me a screenshot of the actual used video memory, in any game of your choice, exceeding the amount of available video memory on your GPU, then the metric will have some value in showing the video memory required to run the game optimally. If you could have done this, i am sure you would have by now though.

I think we'll just have to agree to disagree, unfortunately you have not managed to convince me this time based on my personal testing with two different GPUs.

As long as the frame time graphs do not show any spikes, it won't matter if your FPS are 45 or 95 as long as they are consistent. Here is a video showing you how to setup the frame time graphs. https://www.youtube.com/watch?v=8Kskk5tEBx8

EDIT

I clearly explained Frosty how i tested this with an 8GB GPU and a 16GB GPU. If you do not believe me that's okay, but i am surprised that you said this.

I think that is me bowing out now, i wish you all the best.

But it won't because it cannot, the game engine requests certain amount of vRAM from the video card/drivers and the driver allocates it that much memory. That is how much physically addressable memory the engine has to store assets in unless it makes a request to the driver to be allocaed some more or some less. If it tried to address memory that was outside of the range that the video drivers had assigned to it (i.g Mem used exceeded mem allocated) then it would just crash because that memory address doesn't exist and it would get an error back from the drivers telling it that.

The drivers are king, they constrain the game to accessing memory on the GPU by only allowing it to address a private range of addresses which are allocated to the game, otherwise it could just interfere with memory allocated to other processes. Once you've been allocated that much vRAM you cannot use more than it. If you tried to the GPU would basically resort to paging data out to disk which is when you get your frame rate tanking down to almost nothing and THAT is when you would get hitching.

I know how to set up fame time, I've done it already and recorded me getting in a vehicle where my last recording left off and driving it across zone borders into the next area and the frame time remains at about 20ms with deviations of just a few ms. There's no visible hitching what so ever. And that's with the game being recorded on the same video card. Do you want me to upload the footage? Or are you just going to add another condition post-hoc. I mean if you are then can you just tell me precise conditions you mean when you say "optimal" up front then I can meet all the conditions first, then upload footage so hopefully you're as close to satisfied as possible.

I don't doubt your experiences, even despite purely taking your word for it. I'm just giving you mine, along with video evidence of what the vRAM allocation is, what the vRAM usage is (what the game is actually addressing) which has been verified by multiple 3rd parties. It was verified by a load of the FS2020 geeks to match almost precisely with what the games internal metrics say about vRAM use and why that is less than external tools report. There's several huge threads on this forum and others detailing why this is the case. In this case the metric I'm using (memory used) lines up not only with what the FC5 video menu estimates for my vRAM usage (about 5.7Gb) but also what the internal benchmark metric tells you is used at the end of the benchmark. Again, this is about 5.7Gb which is what memory used shows, and specifically being lower than what is allocated which was about 7.5Gb at the time.

Maybe the difference is explained some other way, maybe your FOV is amplified up with a super wide resolution (mine is custom set to pretty wide already at 106 which is near the upper end of the scale) or maybe you have processes on your computer running that interfere with the games performance in some way, or maybe AMD video card drivers are not well optimized for FC5 I have no idea, there's loads of things that can explain hitching. Are you loading the game off your 970 Evo Pro SSD or your HDD?

The last quote you have of me I said to make a point, specifically that by YOUR requirements and metrics of measurement of what would constitute the game running optimally your own 16Gb card would probably fail when tested against a 24Gb 3090, but probably not until having loaded some more assets.

Also lastly, as for hitching, I mean the entire video of my play through is there now in 1080p60 although 4k is still processing. And I get in a heli and fly through multiple zones rapidly transitioning from air to ground, you can see the vRAM in use is dropping to 4Gb and then fill to 6Gb in extremely short time spans and there's no visible hitching. I don't even know why you'd demand a frame time graph, if you cannot visibly see hitching why do you need a graph? If you're precise about what would satisfy you in terms of evidence then I'll do that and upload it and you can make your mind up, but I'm not going to play a game of move the goal posts every time I upload, let's just agree ahead of time what the requirements are for "optimally playable", including what constitutes a hitch for you.

 

[fantasticCG]

Ahh so if it can't be maxed settings at 60fps at 4K it doesn't really count?

Well its a bit misleading to be honest I watched the DF dirt 5 video "we do 4k 60 but there's 3 different options to choose from! So you'll have to pick"

When on PC all those options can be combined into one 4k ultra settings 60hz+ and you don't have to choose this and that.

 

[UnderToker]

16gb is more than enough
I have the 24gb 3090 Strix oc I’ll,never need more then about 12gb currently for any of the current gen games , if we ever see cyberpunk maybe a bit more at 4K
Who knows what devs will churn out in the next couple of years , but I’d be more than happy with 16gb knowing it would cover anything

 

[PrincessFrosty]

16gb is more than enough
I have the 24gb 3090 Strix oc I’ll,never need more then about 12gb currently for any of the current gen games , if we ever see cyberpunk maybe a bit more at 4K
Who knows what devs will churn out in the next couple of years , but I’d be more than happy with 16gb knowing it would cover anything

Do you have FarCry5?

 

[Grim5]

16gb is more than enough
I have the 24gb 3090 Strix oc I’ll,never need more then about 12gb currently for any of the current gen games , if we ever see cyberpunk maybe a bit more at 4K
Who knows what devs will churn out in the next couple of years , but I’d be more than happy with 16gb knowing it would cover anything

please delete post

 

[Nablaoperator]

Huh? No it's not pointless, it's telling you what the game is genuinely using on your hardware.

Basis new data, it seems memory allocation (and hence utilisation) can be a control target in itself. We will need more data, vram utilisation as a standalone metric doesn't make much sense.

Typically you'd not like GPU to miss vram. Anything to that effect has to be measured.

 

[Kaapstad]

Yes
/Thread.

 

[TNA]

Yes
/Thread.

+1

 

[Dave2150]

But it won't because it cannot, the game engine requests certain amount of vRAM from the video card/drivers and the driver allocates it that much memory. That is how much physically addressable memory the engine has to store assets in unless it makes a request to the driver to be allocaed some more or some less. If it tried to address memory that was outside of the range that the video drivers had assigned to it (i.g Mem used exceeded mem allocated) then it would just crash because that memory address doesn't exist and it would get an error back from the drivers telling it that.

The drivers are king, they constrain the game to accessing memory on the GPU by only allowing it to address a private range of addresses which are allocated to the game, otherwise it could just interfere with memory allocated to other processes. Once you've been allocated that much vRAM you cannot use more than it. If you tried to the GPU would basically resort to paging data out to disk which is when you get your frame rate tanking down to almost nothing and THAT is when you would get hitching.

I know how to set up fame time, I've done it already and recorded me getting in a vehicle where my last recording left off and driving it across zone borders into the next area and the frame time remains at about 20ms with deviations of just a few ms. There's no visible hitching what so ever. And that's with the game being recorded on the same video card. Do you want me to upload the footage? Or are you just going to add another condition post-hoc. I mean if you are then can you just tell me precise conditions you mean when you say "optimal" up front then I can meet all the conditions first, then upload footage so hopefully you're as close to satisfied as possible.

I don't doubt your experiences, even despite purely taking your word for it. I'm just giving you mine, along with video evidence of what the vRAM allocation is, what the vRAM usage is (what the game is actually addressing) which has been verified by multiple 3rd parties. It was verified by a load of the FS2020 geeks to match almost precisely with what the games internal metrics say about vRAM use and why that is less than external tools report. There's several huge threads on this forum and others detailing why this is the case. In this case the metric I'm using (memory used) lines up not only with what the FC5 video menu estimates for my vRAM usage (about 5.7Gb) but also what the internal benchmark metric tells you is used at the end of the benchmark. Again, this is about 5.7Gb which is what memory used shows, and specifically being lower than what is allocated which was about 7.5Gb at the time.

Maybe the difference is explained some other way, maybe your FOV is amplified up with a super wide resolution (mine is custom set to pretty wide already at 106 which is near the upper end of the scale) or maybe you have processes on your computer running that interfere with the games performance in some way, or maybe AMD video card drivers are not well optimized for FC5 I have no idea, there's loads of things that can explain hitching. Are you loading the game off your 970 Evo Pro SSD or your HDD?

The last quote you have of me I said to make a point, specifically that by YOUR requirements and metrics of measurement of what would constitute the game running optimally your own 16Gb card would probably fail when tested against a 24Gb 3090, but probably not until having loaded some more assets.

Also lastly, as for hitching, I mean the entire video of my play through is there now in 1080p60 although 4k is still processing. And I get in a heli and fly through multiple zones rapidly transitioning from air to ground, you can see the vRAM in use is dropping to 4Gb and then fill to 6Gb in extremely short time spans and there's no visible hitching. I don't even know why you'd demand a frame time graph, if you cannot visibly see hitching why do you need a graph? If you're precise about what would satisfy you in terms of evidence then I'll do that and upload it and you can make your mind up, but I'm not going to play a game of move the goal posts every time I upload, let's just agree ahead of time what the requirements are for "optimally playable", including what constitutes a hitch for you.

Multiple third parties, and thousands of end users have already demonstrated that games are already using 8-10GB at 4K. Multiple people have already witnessed 8GB cards stuttering due to lack of VRAM. It's only a matter of time until the 3080 10GB experiences this, sooner than later what with the new consoles (with double the total memory) launching in days.

Not much more to it than that tbh.

 

[RBImGuy]

The future will bypass this due to PC at some point will stream assists and bypass the way its handled today.
Can check how Ps5 handles this for a reference.
Its not like engineers are unaware how game engines works but they still have to create the needed hardware and in some cases build the eco system up.
Like atm ray tracing in its infancy, like VR still is.
As we seen with amd have designed bandwidth as its been an issue for cards and still is for Nvidia.
next generation apu and such will have big navi designs and have massive bandwidth available.
one thing at the time and slowly we have better hardware like the big navis

 

[Dave2150]

The future will bypass this due to PC at some point will stream assists and bypass the way its handled today.
Can check how Ps5 handles this for a reference.
Its not like engineers are unaware how game engines works but they still have to create the needed hardware and in some cases build the eco system up.
Like atm ray tracing in its infancy, like VR still is.
As we seen with amd have designed bandwidth as its been an issue for cards and still is for Nvidia.
next generation apu and such will have big navi designs and have massive bandwidth available.
one thing at the time and slowly we have better hardware like the big navis

Not correct.

PS5 NVME caching is to do with game loading speed, to load games quickly into RAM. It doens't reduce the amount of VRAM required. Common sense says that if it did, they wouldn't have put 16GB total memory on the PS5, would they?