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The video RAM information guide

D2ultima

Oh god blue text. I can't read that.

It's 5:35am and I have no idea if you're serious or joking xD.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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Sorry, you have some incorrect information right in the first couple of points you try to make. I'm not going to break down your entire post, as I'm sure someone else will get to that later, so I'll just tackle the first few things.

You are partially correct that VRAM usage is not 100% restricted by or related to GPU usage, but CoD Ghost is the worst possible example you can use to make that point. CoD Ghosts will simply fill up what ever VRAM buffer your card has, but its not actually using the VRAM. Crysis 3 on ultra and at 4K resolution does not use 4GB of VRAM, so there is no way CoD Ghost is using it. Games also "reserve" additional VRAM that does not actually get used. Just like Windows will reserve more system RAM based on the total amount of RAM you install. The issue with VRAM is in games that actually need high amounts of VRAM will more often than not run into a limitation of the GPU's processing power.

There is no game in existence that needs and will use 4GB of VRAM where you would not first be limited by the processing power of something like a 4GB GTX 760. There are games that need and will use more than 2GB of VRAM, and a 760 can power those games, but in order to provide that extra VRAM the easiest and cheapest solution was to use an extra stick of VRAM. This leads into the second issue with VRAM totals being determined by the bus size. You can't stick 2.5GB or 3GB of VRAM on a 256bit bus, so the only option is to bump it up to 4GB.

VRAM totals are absolutely determined by the bus width. The bus size will determine the quantity in which VRAM can be added. 
A 128bit, 256bit or 512bit bus will use values of 128, 256, 512, 1024, 2048, 4096 or 8192 MB of VRAM.
A 192bit or 384bit bus will use values of 192, 384, 768, 1536, 3072 or 6144 MBof VRAM.
So yes you can stick 8192MB of VRAM on a 128bit bus, but you will never in a 100 years be capable of achieving a memory clock rate that will be capable of using all that VRAM on such a small bus size.


 

i7 2600K @ 4.7GHz/ASUS P8Z68-V Pro/Corsair Vengeance LP 2x4GB @ 1600MHz/EVGA GTX 670 FTW SIG 2/Cooler Master HAF-X

 

http://www.speedtest.net/my-result/3591491194

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See? Good. I can update that now. I only noticed real-world applications of it. And yes, I was told that Ghosts probably just filling up the buffer. The point was though, that it can still be used up. Also, seeing as how I can put titanfall on mostly medium settings but insane textures, YES, most of the 4GB vRAM buffer on a 760 can be used up. It is not practical, however, I do agree on that point, but it is possible. I'll add another point about that via screenshot. The main purpose of my showing CoD: Ghosts there was to show that the vRAM buffer can be used up without a huge amount of power being used. 

 

The rest of your post however, is getting more technical than I was aiming for. I was more meaning to make layman's terms about this; as in "what you could look for to buy". If you want to pick through the rest of the post, and tell me where I went wrong, go ahead. I won't claim to know everything, and I'm glad to fix what I don't know.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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@jmaster299

Decided to tag you in a new post instead

 

If what you said before is true, how did the 192-bit mem bus GTX 660Ti have 2GB of vRAM on it? I saw the trend with the mem bus sizes vs RAM sizes and where you were going, but by your logic, the 660Ti should only be capable of using 1.5GB of that vRAM.

 

Also I covered the game using extra vRAM to prevent texture popping in a further post down the line, I believe.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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Thx for such a big article, that is informational. I'll copy & save it in my facebook notes, in case I'll need to dig deeper on vram theme.

| CPU: i7 3770k | MOTHERBOARD: MSI Z77A-G45 Gaming | GPU: GTX 770 | RAM: 16GB G.Skill Trident X | PSU: XFX PRO 1050w | STORAGE: SSD 120GB PQI +  6TB HDD | COOLER: Thermaltake: Water 2.0 | CASE: Cooler Master: HAF 912 Plus |

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Thx for such a big article, that is informational. I'll copy & save it in my facebook notes, in case I'll need to dig deeper on vram theme.

Not a problem. I just want to be sure anybody that sees if I did something wrong tells me so I can fix it. I don't wanna be the cause of spreading misinformation myself, and my SLI guide is a lot more rock solid than this one xD

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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@jmaster299

Decided to tag you in a new post instead

 

If what you said before is true, how did the 192-bit mem bus GTX 660Ti have 2GB of vRAM on it? I saw the trend with the mem bus sizes vs RAM sizes and where you were going, but by your logic, the 660Ti should only be capable of using 1.5GB of that vRAM.

 

Also I covered the game using extra vRAM to prevent texture popping in a further post down the line, I believe.

Nvidia was either lying or they were using some sort of trickery to achieve that total. 2048 can not be divided evenly by 192. You end up with 10.6666666. The only way they could have done it was with 768 + 1134, which gets them 1914MB of VRAM, which is not technically 2GB.

i7 2600K @ 4.7GHz/ASUS P8Z68-V Pro/Corsair Vengeance LP 2x4GB @ 1600MHz/EVGA GTX 670 FTW SIG 2/Cooler Master HAF-X

 

http://www.speedtest.net/my-result/3591491194

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Nvidia was either lying or they were using some sort of trickery to achieve that total. 2048 can not be divided evenly by 192. You end up with 10.6666666. The only way they could have done it was with 768 + 1134, which gets them 1914MB of VRAM, which is not technically 2GB.

@jmaster299 There have been some cards with that number. 660Ti has 2GB of vRAM according to GPU-Z screenshots

And some other cards have been anomalies too: GTX 650 Ti Boost || GTX 550Ti || GTX 560 SE || GTX 460 v2

 

That being said, I DID see the trend you mentioned; 320-bit memory buses had vRAM amounts like 1280MB and such, which I recognized as being related to each other, but there have been 192-bit cards with 1GB and 2GB of vRAM listed and sold by nVidia. I am less familiar with AMD's lineup as their mobile offerings are not very good compared to the green side, despite being cheaper, so I don't take too much note of their desktop GPUs' power except for direct power comparisons.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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@jmaster299 There have been some cards with that number. 660Ti has 2GB of vRAM according to GPU-Z screenshots

And some other cards have been anomalies too: GTX 650 Ti Boost || GTX 550Ti || GTX 560 SE || GTX 460 v2

 

That being said, I DID see the trend you mentioned; 320-bit memory buses had vRAM amounts like 1280MB and such, which I recognized as being related to each other, but there have been 192-bit cards with 1GB and 2GB of vRAM listed and sold by nVidia. I am less familiar with AMD's lineup as their mobile offerings are not very good compared to the green side, despite being cheaper, so I don't take too much note of their desktop GPUs' power except for direct power comparisons.

GPU-Z says whatever the card tells it to say. Again, it is impossible to divide 2048 by 192, making it impossible for the card to actually have 2048MB of RAM. Companies like that all the time. Its why every single HDD and SSD in existence will claim it has 500GB, when in fact it has 500000MB, which is less than 500GB.

i7 2600K @ 4.7GHz/ASUS P8Z68-V Pro/Corsair Vengeance LP 2x4GB @ 1600MHz/EVGA GTX 670 FTW SIG 2/Cooler Master HAF-X

 

http://www.speedtest.net/my-result/3591491194

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Nvidia was either lying or they were using some sort of trickery to achieve that total. 2048 can not be divided evenly by 192. You end up with 10.6666666. The only way they could have done it was with 768 + 1134, which gets them 1914MB of VRAM, which is not technically 2GB.

 

NVIDIA does indeed use RAM chips with mis-matched capacities to achieve this.

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GPU-Z says whatever the card tells it to say. Again, it is impossible to divide 2048 by 192, making it impossible for the card to actually have 2048MB of RAM. Companies like that all the time. Its why every single HDD and SSD in existence will claim it has 500GB, when in fact it has 500000MB, which is less than 500GB.

@jmaster299 I know the SSDs and HDDs and such are a bit odd, and once formatted have even less space, etc. But as for the GPUs; if one uses a sensor program it should work properly. No matter how you slice it, if I start a game like BF4, run GPU-Z's sensors or Playclaw 5's GPU sensors etc and that vRAM passes 2000MB used, then we've got something. For example, I've never seen my cards pass 4080MB of vRAM being used; and even in the CoD: Ghosts screenshot above you see it stopped at about 4016MB.. so 4096MB is quite likely my actual RAM size. Unfortunately I do not own a 660Ti or any of the affected cards to personally check, though I would love to do some testing on it.

 

As you said, the maximum RAM limit ought to be 1914 at best. 

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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NVIDIA does indeed use RAM chips with mis-matched capacities to achieve this.

I find it funny; I wrote the guide and due to my writing it I'm learning more. I love tech.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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NVIDIA does indeed use RAM chips with mis-matched capacities to achieve this.

Which is exactly what I said in my post. But there is still no way for them to get exactly 2048MB that way. They can get close to it, a little under or over, but never exactly that amount.

 

@jmaster299 I know the SSDs and HDDs and such are a bit odd, and once formatted have even less space, etc. But as for the GPUs; if one uses a sensor program it should work properly. No matter how you slice it, if I start a game like BF4, run GPU-Z's sensors or Playclaw 5's GPU sensors etc and that vRAM passes 2000MB used, then we've got something. For example, I've never seen my cards pass 4080MB of vRAM being used; and even in the CoD: Ghosts screenshot above you see it stopped at about 4016MB.. so 4096MB is quite likely my actual RAM size. Unfortunately I do not own a 660Ti or any of the affected cards to personally check, though I would love to do some testing on it.

 

As you said, the maximum RAM limit ought to be 1914 at best. 

Stop using CoD Ghosts as an example, the RAM usage totals shown when playing that game are not accurate. Also, you have to remember that GPUs can use a combination of VRAM and system RAM, and that's how you can achieve a "usage" greater than the physical amount of VRAM that is installed on the card. Also don't use the info tab on GPU-Z as your basis for what amount of VRAM is being used because GPU-Z is only displaying the number that Nvidia or AMD tells it to display. You would need to do a validation with GPU-Z in order to get that information. That's why the validation function exists, to prove that the base info matches the usage info.

If I run dxdiag on my system, it shows I have an "Approx Memory Total" of 4038MB for my GTX 670 which only has 2GB of VRAM on it. That's how Nvidia can fudge with their numbers and claim that a card with 1914MB of VRAM actually has 2GB of VRAM. The only issue is if a game actually needs to tip into that shared memory pool, you will run into performance issues like GPU usage dropping to 0 because having to pull from that shared memory pool is always slower than using that onboard VRAM.

i7 2600K @ 4.7GHz/ASUS P8Z68-V Pro/Corsair Vengeance LP 2x4GB @ 1600MHz/EVGA GTX 670 FTW SIG 2/Cooler Master HAF-X

 

http://www.speedtest.net/my-result/3591491194

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Stop using CoD Ghosts as an example, the RAM usage totals shown when playing that game are not accurate. Also, you have to remember that GPUs can use a combination of VRAM and system RAM, and that's how you can achieve a "usage" greater than the physical amount of VRAM that is installed on the card. Also don't use the info tab on GPU-Z as your basis for what amount of VRAM is being used because GPU-Z is only displaying the number that Nvidia or AMD tells it to display. You would need to do a validation with GPU-Z in order to get that information. That's why the validation function exists, to prove that the base info matches the usage info.

If I run dxdiag on my system, it shows I have an "Approx Memory Total" of 4038MB for my GTX 670 which only has 2GB of VRAM on it. That's how Nvidia can fudge with their numbers and claim that a card with 1914MB of VRAM actually has 2GB of VRAM. The only issue is if a game actually needs to tip into that shared memory pool, you will run into performance issues like GPU usage dropping to 0 because having to pull from that shared memory pool is always slower than using that onboard VRAM.

@jmaster299 I am fully aware of the shared memory deal. This is why I said using the SENSORS. As in the real-time reporting of the usage. As you said, once you cross the vRAM on the card, it'll significantly slow down. I am also only using ghosts' screenshot as the only example I have on-hand of recorded proof that I pass 4000MB of used vRAM while remaining under the 4096MB limit. You need to read what I say. I've seen it cross 4000 on Titanfall before, which is where I saw the maximum usage of 4080MB that one time. I do not, however, have a screenshot of it. It is simply in my memory.

 

Next, my GPU usually reads on validation processes as having over 6GB of vRAM, just like yours does. My old 280M read as having 3800MB when it was a 1GB card. I know this happens, however I've never before via sensor programs seen the vRAM pass what was on the card itself, which is again why I mentioned looking at SENSOR programs.

 

Anyway, I suppose I've seen enough proof from both you and linus to assume that their RAM sizes are close but no cigar and they round it off and fiddle with the vBIOS for desired effect. I'm not yet sure how I'll update this to fit in the guide, but I'll think of something. Section fixed; full RAM exists, with a bit of a twist. Thanks for the information. Like I said, anything else in the guide you see that's incorrect, let me know.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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This is a good read to show how Nvidia uses 2GB of ram for a 192 bit bus. Either way mentioned there seems to have compromises when utilizing that last 512mb, but that doesn't mean that the card can't use the full 2GB it has.

http://www.anandtech.com/show/6159/the-geforce-gtx-660-ti-review/2

i5 4690k  -  MSI Z97M Gaming  -  GTX 970  -  Kingston HyperX Savage  -  Samsung 840 EVO  -  Phanteks Enthoo EVOLV

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This is a good read to show how Nvidia uses 2GB of ram for a 192 bit bus. Either way mentioned there seems to have compromises when utilizing that last 512mb, but that doesn't mean that the card can't use the full 2GB it has.

http://www.anandtech.com/show/6159/the-geforce-gtx-660-ti-review/2

And we have found that nVidia did not lie, but still uses tricks. Wonderful! =D. Now I really know what to update my guide with. Thanks!

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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And we have found that nVidia did not lie, but still uses tricks. Wonderful! =D. Now I really know what to update my guide with. Thanks!

Which is what I said. They either lied or used "Trickery" to get those numbers. But you have to keep in mind that the exception does not make the rule. The bus size determining the amount of VRAM is true 99.9% of the time. A couple of one off cases from Nvidia doesn't change the rule.

i7 2600K @ 4.7GHz/ASUS P8Z68-V Pro/Corsair Vengeance LP 2x4GB @ 1600MHz/EVGA GTX 670 FTW SIG 2/Cooler Master HAF-X

 

http://www.speedtest.net/my-result/3591491194

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Which is what I said. They either lied or used "Trickery" to get those numbers. But you have to keep in mind that the exception does not make the rule. The bus size determining the amount of VRAM is true 99.9% of the time. A couple of one off cases from Nvidia doesn't change the rule.

I know, and if you check the section I added in the guide above I definitely mentioned both your method and what nVidia did for their other cards like the 550Ti and 660Ti, along with the link he gave us. So I think that should be cleared up. Thanks for proving me wrong though, I'm always happy to make sure I spread the least misinformation possible around. The more people can legitimately prove me wrong, the better, because when I do stuff like this, it makes sure the quality is improved, and I don't tell people garbage elsewhere.

I have finally moved to a desktop. Also my guides are outdated as hell.

 

THE INFORMATION GUIDES: SLI INFORMATION || vRAM INFORMATION || MOBILE i7 CPU INFORMATION || Maybe more someday

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