IMO it probably won't make a difference, except possibly at high levels of AA.
But I've never run benchmarks to confirm it, I have seen benchmarks that show 1 vs 2GB does matter to surround, so perhaps there is a real difference.
Running in 3D vs. 2D does not increase memory usage.
3D does not render 2 frames at the same time, it renders them one of a time, just twice as frequently compared to 2D at same frame rate.
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
Running in 3D vs. 2D does not increase memory usage.
3D does not render 2 frames at the same time, it renders them one of a time, just twice as frequently compared to 2D at same frame rate.
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
I do not have 3D vision so do not take what I am going to say as gospel, however from listening to the people that DO have it they all say VRAM usage increases as opposed to 2D.
I would get the extra VRAM if I were you regardless of wether or not that is true simply because games like Metro2033 and SC2 use a heap of VRAM with AA at high res.
I do not have 3D vision so do not take what I am going to say as gospel, however from listening to the people that DO have it they all say VRAM usage increases as opposed to 2D.
I would get the extra VRAM if I were you regardless of wether or not that is true simply because games like Metro2033 and SC2 use a heap of VRAM with AA at high res.
I have been told by those that have 3D that 3D does indeed increase the vRAM usage significantly. 560 Ti's may not be adequate for a game running 1080p maxed out in 3D.
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
I have been told by those that have 3D that 3D does indeed increase the vRAM usage significantly. 560 Ti's may not be adequate for a game running 1080p maxed out in 3D.
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
[quote name='Gilador' date='12 February 2011 - 10:07 PM' timestamp='1297505273' post='1192571']
I do have 3D Vision and I can say that running game in 3D vs. 2D does not increase GPU memory usage.
It would be nice to put these internet rumors to end, but I am fighting a losing battle....
[/quote]
You wont be able to 'put them to bed' because you are wrong.
Explain how with identical settings I magically use 150mb more VRAM.
This is consistent throughout any game tested.
Mem usage without 3D
[IMG]http://i55.tinypic.com/709gsp.jpg[/IMG]
Mem usage with 3D
[IMG]http://i52.tinypic.com/2yphxr5.jpg[/IMG]
Cool! It would be nice to hear some programmer's view.
All I know is that if I go from 2D to 3D mode and look at my GPU memory usage, it does not go up. I have been looking at my GTA-IV memory usage.
I guess I was over-reacting. I just wanted to make it known that 2D vs. 3D does not double your menory usage, like the OP's "since 2 frames are being rendered at the same time" statement made out it to be.
Cool! It would be nice to hear some programmer's view.
All I know is that if I go from 2D to 3D mode and look at my GPU memory usage, it does not go up. I have been looking at my GTA-IV memory usage.
I guess I was over-reacting. I just wanted to make it known that 2D vs. 3D does not double your menory usage, like the OP's "since 2 frames are being rendered at the same time" statement made out it to be.
==============
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
============
..is kinda useful to figuring out how much memory your GPU should use. Just saying..
Of course the more memory you have, the better off you are for now, or for the future, but it is nice to know how well off you are right now.
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
============
..is kinda useful to figuring out how much memory your GPU should use. Just saying..
Of course the more memory you have, the better off you are for now, or for the future, but it is nice to know how well off you are right now.
[quote name='Goddess84' date='12 February 2011 - 02:14 AM' timestamp='1297505649' post='1192574']
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
[/quote]
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
[quote name='Goddess84' date='12 February 2011 - 02:14 AM' timestamp='1297505649' post='1192574']
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
3D Vision does use more video memory.
Even if NVidia rendered the frames sequentially they would at a bare minimum need 2 front buffers, and two back buffers, since they have to be able to continuously swap them while the next frames are drawn.
If you read the white papers, they duplicate all render targets that do not have a 1:1 aspect ratio.
Having said that unless your running at high AA levels I'm not sure it's a dramatic increase, textures and geometry aren't doubled.
At high AA levels it certainly can add up, but I don't usually bother in 3D.
Even if NVidia rendered the frames sequentially they would at a bare minimum need 2 front buffers, and two back buffers, since they have to be able to continuously swap them while the next frames are drawn.
If you read the white papers, they duplicate all render targets that do not have a 1:1 aspect ratio.
Having said that unless your running at high AA levels I'm not sure it's a dramatic increase, textures and geometry aren't doubled.
At high AA levels it certainly can add up, but I don't usually bother in 3D.
[quote name='Partol' date='12 February 2011 - 01:25 PM' timestamp='1297513559' post='1192613']
From my 3D vision gaming experience,
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
[/quote]This is exactly what happens. If 3d is enabled but not turned on it's doing the 3d-thing anyway, just with a separationlevel of zero. Turning on 3d via hotkey increases the separation to the preset value without using more resources. The only way to see the usage in 2d is completely disabling 3d in the control panel before starting a game.
[quote name='Partol' date='12 February 2011 - 01:25 PM' timestamp='1297513559' post='1192613']
From my 3D vision gaming experience,
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
This is exactly what happens. If 3d is enabled but not turned on it's doing the 3d-thing anyway, just with a separationlevel of zero. Turning on 3d via hotkey increases the separation to the preset value without using more resources. The only way to see the usage in 2d is completely disabling 3d in the control panel before starting a game.
[quote name='FuchiBOT' date='12 February 2011 - 04:23 AM' timestamp='1297513413' post='1192611']
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
[/quote]
Nobody can answer this? I have yet to find a decent explanation on the internets ....
[quote name='FuchiBOT' date='12 February 2011 - 07:23 AM' timestamp='1297513413' post='1192611'][i]So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing...[/i][/quote]
When a GPU runs out of VRAM it turns to the PCIe interface for support through to the system memory. Neither the PCIe nor the system RAM can come close to the on-board VRAM's bandwidth, and as a result your frame rates suffer to added wait states and flushes/reloads due to the cores' being unable to maintain their insruction queues...
[quote name='FuchiBOT' date='12 February 2011 - 07:23 AM' timestamp='1297513413' post='1192611']So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing...
When a GPU runs out of VRAM it turns to the PCIe interface for support through to the system memory. Neither the PCIe nor the system RAM can come close to the on-board VRAM's bandwidth, and as a result your frame rates suffer to added wait states and flushes/reloads due to the cores' being unable to maintain their insruction queues...
"AIO": Intel Xeon E5-2690 v2 @ 103.2 MHz BCLK | ASUS X79-Deluxe | SwifTech Apogee Drive II Pump and Block | 120 mm + 240 mm Push-Pull | 64 GB G.Skill PC3-12800 @ 1924 MHz | NVIDIA RTX 2070 FE | LG 25UM56 UW Monitor | Plextor 1TB PX-1TM9PeY PCIe NVMe (Windows 10 Pro x64 1809) | Plextor 1TB PX-1TM9PeY PCIe NVMe (UserData) | 4x SanDisk 500 GB SSDs in Marvell SATA3 RAID0 (C:\Games) | 2x WD 250 GB SSDs and WD 3 TB RED HDD in Marvell HyperDuo RAID (Media) | 16 GB RAMDisk (Temp Files) | WD My Book Essentials 3 TB NAS (Archives) | LG BP50NB40 ODD | eVGA Supernova G+ 1000 W PSU | Cooler Master HAF-XB
"Gaming": Intel Xeon E5-1650 v2, Turbo 44x (5-6), 45x (3-4), 46x (1-2) | ASUS Rampage IV Extreme | SwifTech Apogee Drive II Pump and Block | 120 mm + 240 mm Push/Pull | 32 GB G.Skill PC3-12800 @ 1866 MHz | NVIDIA GTX 1080 FE | NVIDIA GTX 970 RE | Samsung U28E510 UHD | 2x PNY 480 GB SSDs in Intel SATA3 RAID0 (OS) | Plextor 1TB PX-1TM9PeY PCIe NVMe (Disk Games) | 4x PNY 240 GB SSDs in Intel SATA2 RAID0 (On-Line Games) | eVGA Supernova G+ 1000 W PSU | Cooler Master HAF-XB | Windows 10 Pro x64 1809
Will getting a card with 2gb vs. 1gb offer significant performance gains since 2 frames are being rendered at the same time?
I am running on a 1080p HDTV so no extreme resolutions will be ran.
Thanks in advance.
Will getting a card with 2gb vs. 1gb offer significant performance gains since 2 frames are being rendered at the same time?
I am running on a 1080p HDTV so no extreme resolutions will be ran.
Thanks in advance.
i7-4770k @ 4.0ghz - Kraken X60 | Asus Strix 1080 OC | 32gb Corsair Vengeance Pro 2400mhz | MSI Z97 Gaming 5 | XFX PRO 850w Black Edition | Corsair Carbide Air 540 | Win10 Pro | U.S.A.
But I've never run benchmarks to confirm it, I have seen benchmarks that show 1 vs 2GB does matter to surround, so perhaps there is a real difference.
But I've never run benchmarks to confirm it, I have seen benchmarks that show 1 vs 2GB does matter to surround, so perhaps there is a real difference.
My Blog
3D does not render 2 frames at the same time, it renders them one of a time, just twice as frequently compared to 2D at same frame rate.
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
3D does not render 2 frames at the same time, it renders them one of a time, just twice as frequently compared to 2D at same frame rate.
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
I would get the extra VRAM if I were you regardless of wether or not that is true simply because games like Metro2033 and SC2 use a heap of VRAM with AA at high res.
I would get the extra VRAM if I were you regardless of wether or not that is true simply because games like Metro2033 and SC2 use a heap of VRAM with AA at high res.
CPU: Core i7 930 @ 4.20ghz 1.3v cooled by Antec Kuhler 920
MOBO: Asus P6X58D Premium
GFX: 2x Asus GTX 560Ti Direct CUII @ 900mhz Core 2200mhz Memory
RAM: Corsair CMG6GX3M3A1600C7 6gb 1600mhz 7-7-7-20 2t
PSU: Thermaltake Toughpower 850 watt
CASE: Antec 1200
APU: X-fi Titanium Fatality SPEAKERS: Logitech X-530 5.1
HDD: 1x OCZ Agility 3 60gb SSD GAMES 2x Western Digital Caviar Black 500gb in RAID 0
DISPLAY: Acer H243HX 24" @ 1920x1080 Resolution
KEYBOARD: Logitech G19 MOUSE: Logitech G5 WHEEL Logitech G25 JOYSTICK Logitech G940
OPERATING SYSTEM: Windows 7 Ultimate x64 RTM
It would be nice to put these internet rumors to end, but I am fighting a losing battle....
It would be nice to put these internet rumors to end, but I am fighting a losing battle....
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
CPU: i7 3930k @ 4.2GHz 1.21V ~ Motherboard: Asus RoG Rampage IV Extreme
RAM: G.Skill Sniper Gaming Series (4x4GB @ 2133MHz, 9-11-10-28-2T 1.65V)
GPUs: 1x R9 280X Vapor-X (Games/F@H), 1x R9 290 Core Edition (F@H), 1x R9 290X Core Edition (F@H)
PSU: LEPA G 1600W (Hate it, don't buy it) ~ Case: Enermax Fulmo GT
SSDs/HDDs: Corsair Force3 240GB, Corsair Force3 90GB, 1x Seagate Momentus XT 750GB
OS: Windows 7 Ultimate ~ Display: Sony Bravia 52" LED LCD HDTV
Laptops: Alienware M18x (2013, GTX 560M SLi) & Alienware M14x (2014, GTX 765M)
I do have 3D Vision and I can say that running game in 3D vs. 2D does not increase GPU memory usage.
It would be nice to put these internet rumors to end, but I am fighting a losing battle....
[/quote]
You wont be able to 'put them to bed' because you are wrong.
Explain how with identical settings I magically use 150mb more VRAM.
This is consistent throughout any game tested.
Mem usage without 3D
[IMG]http://i55.tinypic.com/709gsp.jpg[/IMG]
Mem usage with 3D
[IMG]http://i52.tinypic.com/2yphxr5.jpg[/IMG]
I do have 3D Vision and I can say that running game in 3D vs. 2D does not increase GPU memory usage.
It would be nice to put these internet rumors to end, but I am fighting a losing battle....
You wont be able to 'put them to bed' because you are wrong.
Explain how with identical settings I magically use 150mb more VRAM.
This is consistent throughout any game tested.
Mem usage without 3D
Mem usage with 3D
// Owned: MX420 // MX440 // FX5200 Ultra // 7600GT // 8800GTS 320MB // 9800GX2 // GTX275 // SLI GTX580s // SLI GTX780Tis //
________________________________________________________________________________________________________________________
All I know is that if I go from 2D to 3D mode and look at my GPU memory usage, it does not go up. I have been looking at my GTA-IV memory usage.
I guess I was over-reacting. I just wanted to make it known that 2D vs. 3D does not double your menory usage, like the OP's "since 2 frames are being rendered at the same time" statement made out it to be.
All I know is that if I go from 2D to 3D mode and look at my GPU memory usage, it does not go up. I have been looking at my GTA-IV memory usage.
I guess I was over-reacting. I just wanted to make it known that 2D vs. 3D does not double your menory usage, like the OP's "since 2 frames are being rendered at the same time" statement made out it to be.
==============
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
============
..is kinda useful to figuring out how much memory your GPU should use. Just saying..
Of course the more memory you have, the better off you are for now, or for the future, but it is nice to know how well off you are right now.
==============
One really nice feature of EVGA Precision is that it can show your GPU memory usage. If you have a keyboard with LCD display, like G15 from Logitech, you can show the memory usage in the LCD, but it also allows you to superimpose it on your screen, along with FPS, fan speed and temperature, etc.
If your game does not exceed your GPUs memory size, adding more memory will not make any difference. If it maxes it (if you have 1GB card and EVGA Precision shows memory usage in 1GB range always), chances are that more memory would help. Very nice and easy way to estimate if your video card's memory is not enough.
============
..is kinda useful to figuring out how much memory your GPU should use. Just saying..
Of course the more memory you have, the better off you are for now, or for the future, but it is nice to know how well off you are right now.
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
[/quote]
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
Example: Running Crysis, maxed out, in 2D, 1080p, 16xQ AA with a distance-mod, I saw vRAM usage of 1322MB... that's more than most stock cards have, 'cept for 480s and 580s of course. If I woulda been playing in 3D, can you say vRAM cap much?
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
Thief 1/2/gold in 3D
https://forums.geforce.com/default/topic/523535/3d-vision/thief-1-2-and-system-shock-2-perfect-3d-with-unofficial-patch-1-19
http://photos.3dvisionlive.com/Partol/album/509eb580a3e067153c000020/
[Acer GD245HQ - 1920x1080 120Hz] [Nvidia 3D Vision]
[MSI H81M-P33 with Pentium G3258 @ 4.4GHz and Zalman CNPS5X}[Transcend 2x2GB DDR3]
[Asus GTX 750 Ti @ 1350MHz] [Intel SSD 330 - 240GB]
[Creative Titanium HD + Beyerdynamic DT 880 (250ohm) headphones] [Windows 7 64bit]
Even if NVidia rendered the frames sequentially they would at a bare minimum need 2 front buffers, and two back buffers, since they have to be able to continuously swap them while the next frames are drawn.
If you read the white papers, they duplicate all render targets that do not have a 1:1 aspect ratio.
Having said that unless your running at high AA levels I'm not sure it's a dramatic increase, textures and geometry aren't doubled.
At high AA levels it certainly can add up, but I don't usually bother in 3D.
Even if NVidia rendered the frames sequentially they would at a bare minimum need 2 front buffers, and two back buffers, since they have to be able to continuously swap them while the next frames are drawn.
If you read the white papers, they duplicate all render targets that do not have a 1:1 aspect ratio.
Having said that unless your running at high AA levels I'm not sure it's a dramatic increase, textures and geometry aren't doubled.
At high AA levels it certainly can add up, but I don't usually bother in 3D.
My Blog
From my 3D vision gaming experience,
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
[/quote]This is exactly what happens. If 3d is enabled but not turned on it's doing the 3d-thing anyway, just with a separationlevel of zero. Turning on 3d via hotkey increases the separation to the preset value without using more resources. The only way to see the usage in 2d is completely disabling 3d in the control panel before starting a game.
From my 3D vision gaming experience,
Start new game in 2D,
then enable 3D
Vram usage increases ~200-400MB +- 100MB
Start new game in 3D,
turn off 3D
vram usage does not decrease
I think this is the source of the confusion
Disable Stereoscopic 3D in the nvidia control panel in order to see true 2D vram usage.
This is exactly what happens. If 3d is enabled but not turned on it's doing the 3d-thing anyway, just with a separationlevel of zero. Turning on 3d via hotkey increases the separation to the preset value without using more resources. The only way to see the usage in 2d is completely disabling 3d in the control panel before starting a game.
Mb: Asus P5W DH Deluxe
Cpu: C2D E6600
Gb: Nvidia 7900GT + 8800GTX
3D:100" passive projector polarized setup + 22" IZ3D
Stereodrivers: Iz3d & Tridef ignition and nvidia old school.
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
[/quote]
Nobody can answer this? I have yet to find a decent explanation on the internets ....
So, I'm curious ... what would be the effect of a game hitting the vRAM cap? How would it impact the performace of the game? I don't know nothing :D
Nobody can answer this? I have yet to find a decent explanation on the internets ....
When a GPU runs out of VRAM it turns to the PCIe interface for support through to the system memory. Neither the PCIe nor the system RAM can come close to the on-board VRAM's bandwidth, and as a result your frame rates suffer to added wait states and flushes/reloads due to the cores' being unable to maintain their insruction queues...
When a GPU runs out of VRAM it turns to the PCIe interface for support through to the system memory. Neither the PCIe nor the system RAM can come close to the on-board VRAM's bandwidth, and as a result your frame rates suffer to added wait states and flushes/reloads due to the cores' being unable to maintain their insruction queues...
"Gaming": Intel Xeon E5-1650 v2, Turbo 44x (5-6), 45x (3-4), 46x (1-2) | ASUS Rampage IV Extreme | SwifTech Apogee Drive II Pump and Block | 120 mm + 240 mm Push/Pull | 32 GB G.Skill PC3-12800 @ 1866 MHz | NVIDIA GTX 1080 FE | NVIDIA GTX 970 RE | Samsung U28E510 UHD | 2x PNY 480 GB SSDs in Intel SATA3 RAID0 (OS) | Plextor 1TB PX-1TM9PeY PCIe NVMe (Disk Games) | 4x PNY 240 GB SSDs in Intel SATA2 RAID0 (On-Line Games) | eVGA Supernova G+ 1000 W PSU | Cooler Master HAF-XB | Windows 10 Pro x64 1809
Stock is Extreme now