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SLI/CF vram question

post #1 of 4
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I have heard people say on here they extra vram such as 3gb vs 2gb would be helpful in crossfire/sli. Is this true? If so why?
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My first build
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Samsung 840 Seagate barracuda 7200rpm samsung sh-224bb DVD Hyper 212 evo 
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post #2 of 4
Crossfire/SLI gains are noticable at higher resolutions. If you plan to run multiple video cards, you are probably using multiple monitors and/or high-resolution monitors. The increase pixel count then requires more memory.

Crossfire/SLI themselves do not benefit from increase memory. It is the excepted usage with higher memory requirements.


Also note, the data sent to GPU memory is duplicated and this is why three 2GB GDDR5 cards still result in only 2GB effective memory.
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post #3 of 4
The point of multi-card set-ups tends to be high resolution/multi-monitors. Which requires more VRAM for textures and such... Two 2gb cards in SLI is effectively 2gb of Vram, not 4. So a higher VRAM is more beneficial to a set up like SLI/CF that will most likely get used in high resolutions.
    
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post #4 of 4
The reason why some people say that more VRAM is important in SLI/CFX is because it requires, at minimum, 3 GPUs for there to even be enough GPU power to utilize the extra memory. Otherwise, you have extra VRAM that is doing nothing but sit there and more likely than not decreasing your possible max overclock.
Also, since people who are spending thousands on GPUs typically have multiple monitors, the VRAM can absolutely help due to the 2-5x increase in pixels needing to be rendered, and when it comes to AA, there's an even bigger penalty.

It's basically a buffer, but if you don't meet the criteria above,, it's a waste.
   
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Z77 Bench-a-lot
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EVGA GTX780Ti Classified K|ngp|n Edition @ 1483... 16GB G.Skill Ripjaws-Z @ DDR3-2248 9-10-9-26 1T Samsung 830 256GB SSD WD10EZEX 1TB HDD 
Hard DriveHard DriveHard DriveHard Drive
WD10EALX 1TB HDD Seagate Barracuda 7200.14 1TB WD3200AAKS 320GB HDD WD5000HHTZ 10krpm 500GB VelociRaptor 
Optical DriveCoolingCoolingCooling
LG/Hitachi Slim DVD-R/W Custom MB-Backside VRM-sinks (Copper) 3x NZXT RF-FX140LB 1-2krpm 98.3CFM Case Fans 2x Corsair SP120-PE Case Fans 
CoolingCoolingCoolingCooling
Heatkiller GTX680 "Hole Edition" Block + Backplate XSPC Single-Bay Res (Single 5.25 bay) EK Multioption Res X2 - Advanced 150 DD "Fill-Port Res" + Fill-Port Fitting (Red) 
CoolingCoolingCoolingCooling
2x MCP35X + Heatsinks/80x15mm Fan XSPC EX420 Alphacool NeXXos UT60 240 6x Bgears Blasters 140mm 1800rpm Fans 
CoolingCoolingCoolingOS
4x Koolance 120x25mm 2600rpm Fans Comp/Rotary Fittings (BP/XSPC/Monsoon) Primoflex Pro LRT - White (1/2x3/4) Windows 7 Professional 64bit  
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Dell P2210Hb 21.5" 1920x1080p Viewsonic VA2012WB 20.1" LCD 1680x1050 Dell U3014 Eizo 27" 1440p 10bit RGB-LED Backlit AH-IPS Panel 
MonitorKeyboardPowerCase
55" LG HDTV (their top 2014 model) Ducky Mechanical (Browns) NZXT HALE90 850W + 8 blown-up AX1200/i's NZXT Switch 810 (White) 
MouseMouse PadAudioAudio
R.A.T.3 + MX510 My Desk GRADO RS1i Headphones Grado PS1000 Headphones 
OtherOtherOtherOther
Bitfenix Hydra Pro Fan Controller 5ch 30W/ch Bitfenix Alchemy Individually-Sleeved Extension... NZXT Individually-Sleeved Front Panel Wires (Bl... Phobya Sleeved 1x3pin-to-4x3pin Fan Splitter 
OtherOtherOther
Sleeved Wires w Paracord myself (no Heatshrink) Custom Front and Top Panels w HexxMesh *In Prog... Working on Custom Pedestal Prototype 
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