SLI Scaling: Can Three GeForce GTX 760s Beat Two 780s?

Test System And Benchmarks

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Test System Configuration
CPUIntel Core i7-4770K: 3.50 GHz, 8 MB Shared L3 Cache, LGA 1150 Overclocked to 4.5 GHz at 1.20 V
MotherboardASRock Z87 Extreme9/AC, BIOS 1.80, PEX 8747 48-Lane PCIe 3.0 Switch
CPU CoolerThermalright MUX-120 with Zalman ZM-STG1 Paste
RAMG.Skill F3-17600CL9Q-16GBXLD (16 GB) XMP-2200 CAS 11 at DDR3-1600 CAS 9 Defaults
GTX 780 GraphicsNvidia GeForce GTX 780: 863-902 MHz GPU, 3 GB GDDR5-6008
GTX 760 GraphicsEVGA 04G-P4-2766-KR: 980-1033 MHz GPU, 4 GB GDDR5-6008
Hard DriveSamsung 840 Series MZ-7PD256, 256 GB SSD
SoundIntegrated HD Audio
NetworkIntegrated Gigabit Networking
PowerCorsair AX860i: ATX12V v2.3, EPS12V, 80 PLUS Platinum
System Software
OSMicrosoft Windows 8 Professional RTM x64
GraphicsNvidia GeForce 331.58 WHQL
ChipsetIntel INF 9.4.0.1017

The biggest issue we face when it comes to testing three-way SLI is that Intel’s fastest mainstream CPUs only have 16 PCIe 3.0 lanes. The LGA 2011 platform is an alternative, though the processor architecture it hosts is one generation older. The other alternative is to use a motherboard with a bridge chip able to turn 16 lanes of PCI Express connectivity into 32. ASRock sent over our lab's first Z87-based platform with the requisite on-board components, its Z87 Extreme9/AC.

The reason bridges work so well is that they’re able to send multiple copies of the same data to each card. Because the members of an SLI array operate on identical information, this has the benefit of multiplying out bandwidth without needing a much more complicated on-die PCI Express controller. A slightly latency penalty is the only noticeable drawback to this approach, since data has to go through one more piece of silicon.

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Games
Battlefield 3Campaign Mode, "Going Hunting" 90-Second Fraps Test Set 1: Medium Quality Defaults (No AA, 4x AF) Test Set 2: Ultra Quality Defaults (4x AA, 16x AF)
Far Cry 3V. 1.05, DirectX 11, 50-Second Fraps "Amanaki Outpost" Test Set 1: High Quality, No AA, Standard ATC, SSAO Test Set 2: Ultra Quality, 4x MSAA, Enhanced ATC, HDAO
F1 2012Steam version, in-game benchmark Test Set 1: High Quality Preset, No AA Test Set 2: Ultra Quality Preset, 8x AA
Metro: Last LightSteam version, Built-In Benchmark, "Frontline" SceneTest Set 1: DX11, Med Quality, 4x AF, Low Blur, No SSAA, No Tesselation, No PhysXTest Set 2: DX11, High Quality, 16x AF, Normal Blur, SSAA, Tesselation Normal, No PhysX
Tomb RaiderSteam version, Built-In Benchmark Test Set 1: High Quality Preset (8x AF, FXAA), Motion Blur, Screen Effects Test Set 2: Ultimate Quality, (16x AF,  FXAA), Tesselation, TressFX
Synthetic Benchmarks
3DMark ProfessionalVersion 1.1, SystemInfo 4.17.0.0, Fire Strike Benchmark (Extreme Off/On)
Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
  • Zac Lloyd-Jones
    Very interesting article. Would have been great to have the GTX 770 SLI'd in there for comparison :).
    Reply
  • rolli59
    Agree with the conclusion totally since after the price drop on the GTX780 I stopped recommending dual GTX760 over the GTX780.
    Reply
  • Amdlova
    770 is the 680 with more hz... 760 is a new nvidia product is a 660ti with more muscle. 760 = 670 in power
    Reply
  • iam2thecrowe
    there are some major fps drops in the sli configurations on bf3, wonder why? did that happen on the single monitor solution? and in other games? crap like that is why i switched my sli config out for a better single card.
    Reply
  • airplanegeek
    would've been interesting to see the 2GB cards in SLI also
    Reply
  • Crashman
    12245834 said:
    there are some major fps drops in the sli configurations on bf3, wonder why? did that happen on the single monitor solution? and in other games? crap like that is why i switched my sli config out for a better single card.
    I checked and found 1 stuck frame on the GTX 780 SLI at 1920x1080. It lasted far less than a second and dropped FPS from 200 (capped) to 54.
    12245939 said:
    would've been interesting to see the 2GB cards in SLI also
    Yes, but the problem is that it's hard to find six cards laying around (three of each), and we quit buying 2GB cards for 3-way SLI a couple years back when they started running out of memory at 2560x1600. It got worse in Surround mode.
    Reply
  • bystander
    I noticed in Tomb Raider that 780 SLI was broken, yet 760 SLI worked well. 780 SLI had worse scores than a single 780 using Surround setups, yet the 760 SLI worked with surround setups quite well. I wonder what is up with that.
    Reply
  • iam2thecrowe
    12246217 said:
    I noticed in Tomb Raider that 780 SLI was broken, yet 760 SLI worked well. 780 SLI had worse scores than a single 780 using Surround setups, yet the 760 SLI worked with surround setups quite well. I wonder what is up with that.

    weird sh!t sometimes happens with multi-card setups. i have owned both crossfire and sli in the last couple years, and now i'm dead set on single card is the only way to go, only takes one game not to work properly to ruin your day. Multi card for me, is only for when the best card available isn't powerful enough for you, or maybe second best card as the best is often overpriced ridiculously.
    Reply
  • giovanni86
    Waiting for Maxwell. Prices on both sides need to come down. Best for single GPU's was $500 with dual gpu's being double the price, i miss old prices.
    Reply
  • Au_equus
    How about 2x 760 v 780 ti and 3x 780 v 2x 780 ti?
    http://www.ocaholic.ch/modules/smartsection/item.php?page=0&itemid=1172
    Reply