Overclock.net › Forums › Intel › Intel CPUs › Choice of i7 processors?
New Posts  All Forums:Forum Nav:

Choice of i7 processors? - Page 7

post #61 of 63
Quote:
Originally Posted by sonarctica View Post

PLX?

It's an integrated circuit technology that utilizes switching to offer "more" PCIe lanes. Here is a decent Anandtech article from this time last year talking about it.
Warning: Spoiler! (Click to show)
With only sixteen PCIe 3.0 lanes available on a Z77 motherboard paired with an Ivy Bridge CPU, when we get to three or four-way GPU solutions these GPUs are itching to get more bandwidth. The Z77 specification limits us to three GPUs anyway, at x8/x4/x4. For some extra cost on the motherboard, we can add in a PLX PEX 8747 chip that effectively increases our PCIe 3.0 lane count, giving 32 PCIe 3.0 lanes overall.

From what I understand, while the mainstream non-PLX Z77 motherboards support a maximum of 16 PCIe 3.0 lanes (w/IVB cpus), X79 motherboards can support 48 PCIe lanes w/SB-E CPUs. I'm assuming that once IB-E is released these 48 lanes will be PCIe 3.0 also. Having only 16x PCIe 3.0 lanes limits the number of lanes for multi GPU setups, so manufacturers include the PLX PEX 8747 chip (or some other variant I guess), to emulate more lanes by switching. At least, this is how I understood it. My guess is this undoubtedly isn't as optimized as actually having more lanes, and probably presents some adverse effects, perhaps latency issues at the very least based on the diagram. This is why I said that if I knew that I wanted a multi-card setup (2+) from the get go, I would have purchased an X79 platform. I also like how they will be releasing an i7-4820k(?) which will bring unlocked affordable quad-cores to the X79 platform.

I did recently run into this motherboard, and was blown away at how they combined PLX with an X79 platform. Using an SB-E it allows for 64 PCIe lanes! They were able to include x16/x16/x16/x16 PCIe socket system WITH a built in LSI RAID controller. Technology moves so damn fast, biggrin.gif

I hope that answers your question. And again, correct me if I'm wrong smile.gif
Kid Dynomite
(38 items)
 
Black Dynamite
(39 items)
 
 
CPUMotherboardGraphicsRAM
Core i7-4790k @4.8GHz (1.291V) De-Lidded Gigabyte GA-Z87X-OC Force AMD R9 290x 1075/1375 Crucial Ballistix Tactical 32GB @1600MHz 8-8-8 ... 
Hard DriveHard DriveHard DriveHard Drive
Samsung 840 Pro 512GB Samsung M8 1TB 2.5" x4 Samsung F4EG 2TB x3 Seagate SV35 2TB x2 
Hard DriveHard DriveOptical DriveCooling
Seagate Barracuda LP 2TB x2 WD Caviar Green 2TB x1 Sony BD-5850H w/Silverstone FP58 Koolance 380i 
CoolingCoolingCoolingCooling
2x Swiftech MCP655B D5 Pumps XSPC M20 to G1/4" Fillport 1x Bitspower 90-degree Single Rotary 1x Bitspower 20mm g1/4 extender 
CoolingCoolingCoolingCooling
2x Bitspower 10mm g1/4 extenders 2x Bitspower D-Plug Sets (BP-MBWP-C07) 2x Bitspower 3/8"ID x 1/2"OD Compression Fittings 1x Bitspower 1/2"ID x 3/4"OD Single Rotary Comp... 
CoolingCoolingCoolingCooling
4x Bitspower 1/2"ID x 3/4"OD 45-degree Dual Rot... 3x Bitspower 1/2"ID x 3/4"OD 90-degree Triple R... 1x Bitspower 45-degree Single Rotary Koolance VID-AR290X Rev 1.0  
CoolingCoolingCoolingCooling
EK-FB GA Z87X-OC Force PrimoChill PrimoFlex Advanced LRT Tubing 3/8"ID... PrimoChill PrimoFlex Advanced LRT Tubing 1/2"ID... Magicool Extreme Triple 180mm x 35mm Slim Radiator 
CoolingOSMonitorKeyboard
Koolance RP-452X2 Rev2.0 Windows 7 Professional x64 Dell Ultrasharp 2408WFP Corsair K90 
PowerCaseMouseMouse Pad
Seasonic X-1250XM2 Silverstone FT02 (Modified) Razer Naga 2012 Sony Playstation 3 Mouse Pad 
AudioAudioOther
ASUS Xonar Essence STX Logitech Z-5500 Digital IBM M1115 (LSI 9211-8i IT mode) 
  hide details  
Reply
Kid Dynomite
(38 items)
 
Black Dynamite
(39 items)
 
 
CPUMotherboardGraphicsRAM
Core i7-4790k @4.8GHz (1.291V) De-Lidded Gigabyte GA-Z87X-OC Force AMD R9 290x 1075/1375 Crucial Ballistix Tactical 32GB @1600MHz 8-8-8 ... 
Hard DriveHard DriveHard DriveHard Drive
Samsung 840 Pro 512GB Samsung M8 1TB 2.5" x4 Samsung F4EG 2TB x3 Seagate SV35 2TB x2 
Hard DriveHard DriveOptical DriveCooling
Seagate Barracuda LP 2TB x2 WD Caviar Green 2TB x1 Sony BD-5850H w/Silverstone FP58 Koolance 380i 
CoolingCoolingCoolingCooling
2x Swiftech MCP655B D5 Pumps XSPC M20 to G1/4" Fillport 1x Bitspower 90-degree Single Rotary 1x Bitspower 20mm g1/4 extender 
CoolingCoolingCoolingCooling
2x Bitspower 10mm g1/4 extenders 2x Bitspower D-Plug Sets (BP-MBWP-C07) 2x Bitspower 3/8"ID x 1/2"OD Compression Fittings 1x Bitspower 1/2"ID x 3/4"OD Single Rotary Comp... 
CoolingCoolingCoolingCooling
4x Bitspower 1/2"ID x 3/4"OD 45-degree Dual Rot... 3x Bitspower 1/2"ID x 3/4"OD 90-degree Triple R... 1x Bitspower 45-degree Single Rotary Koolance VID-AR290X Rev 1.0  
CoolingCoolingCoolingCooling
EK-FB GA Z87X-OC Force PrimoChill PrimoFlex Advanced LRT Tubing 3/8"ID... PrimoChill PrimoFlex Advanced LRT Tubing 1/2"ID... Magicool Extreme Triple 180mm x 35mm Slim Radiator 
CoolingOSMonitorKeyboard
Koolance RP-452X2 Rev2.0 Windows 7 Professional x64 Dell Ultrasharp 2408WFP Corsair K90 
PowerCaseMouseMouse Pad
Seasonic X-1250XM2 Silverstone FT02 (Modified) Razer Naga 2012 Sony Playstation 3 Mouse Pad 
AudioAudioOther
ASUS Xonar Essence STX Logitech Z-5500 Digital IBM M1115 (LSI 9211-8i IT mode) 
  hide details  
Reply
post #62 of 63
3770k does not have sufficient pci-e lanes to provide the minimum of 8x pci-e 2.0 bandwidth for more than two cards, which is required to run SLI, and so a PLX chip is added to provide additional lanes to enable this. However, PLX does not add any more bandwidth to the CPU, which can introduce latency issues.
post #63 of 63
Quote:
Originally Posted by Fulvin View Post

3770k does not have sufficient pci-e lanes to provide the minimum of 8x pci-e 2.0 bandwidth for more than two cards, which is required to run SLI, and so a PLX chip is added to provide additional lanes to enable this. However, PLX does not add any more bandwidth to the CPU, which can introduce latency issues.

Thus creating bottle-necking right?

Quite a bit of good information in this thread that I had questions about myself, thanks!
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Intel CPUs
Overclock.net › Forums › Intel › Intel CPUs › Choice of i7 processors?