Overclock.net › Forums › Intel › Intel CPUs › Cpu llc?
New Posts  All Forums:Forum Nav:

Cpu llc?

post #1 of 41
8/10/09 at 9:49pm
Thread Starter 
What is CPU LLC? In this forum http://www.overclock.net/intel-cpus/...ease-read.html they either say no LLC or LLC. What's the difference between on or off? Whta does it do? thanks.
My System
(13 items)
  		  
CPUMotherboardGraphicsRAM
q9550 GIGABYTE GA-EP45-UD3R LGA 775 Intel P45 ATX Intel XFX HD 4890 4gb corsair dual channel 800mhz 
Hard DriveOptical DriveOSMonitor
Western Digital Caviar Black Pioneer DVR-2910 Windows 7 Ultimate Samsung SyncMaster P2350 
PowerCase
corsair 650TX NZXT TEMPEST Crafted Series CS-NT-TEM-B Black Stee 
  hide details  
Reply
My System
(13 items)
  		  
CPUMotherboardGraphicsRAM
q9550 GIGABYTE GA-EP45-UD3R LGA 775 Intel P45 ATX Intel XFX HD 4890 4gb corsair dual channel 800mhz 
Hard DriveOptical DriveOSMonitor
Western Digital Caviar Black Pioneer DVR-2910 Windows 7 Ultimate Samsung SyncMaster P2350 
PowerCase
corsair 650TX NZXT TEMPEST Crafted Series CS-NT-TEM-B Black Stee 
  hide details  
Reply
post #2 of 41
8/10/09 at 9:51pm
LLC (Load Line Calibration) helps eliminate vDroop, at least that is what my motherboard says..

Most people (including me) have it enabled.
Ace
(19 items)
  		  
CPUMotherboardGraphicsRAM
Intel i5 3570k @ 4.5Ghz ASRock Z77E-ITX EVGA GTX 680 Hydro Copper G.Skill Ares Series 16GB 1600MHz 
Hard DriveHard DriveOptical DriveCooling
Samsung 840 PRO Series 256GB WD Caviar Black 1TB Asus External Swiftech MCR220-XP 
CoolingCoolingCoolingOS
Swiftech MCR120-XP EK Supreme HF Swiftech MCP355 Windows 8 Professional Plus MC 64-Bit 
MonitorMonitorKeyboardPower
LG W2442PA 24" 1080P LG W2442PA 24" 1080P Das Keyboard Model S Professional Silverstone ST45SF-G 450W SFX  
CaseMouseMouse Pad
Compact Splash - Coming April 2013 Mionix Naos 5000 Steelseries 4HD 
View all
  hide details  
Reply
Ace
(19 items)
  		  
CPUMotherboardGraphicsRAM
Intel i5 3570k @ 4.5Ghz ASRock Z77E-ITX EVGA GTX 680 Hydro Copper G.Skill Ares Series 16GB 1600MHz 
Hard DriveHard DriveOptical DriveCooling
Samsung 840 PRO Series 256GB WD Caviar Black 1TB Asus External Swiftech MCR220-XP 
CoolingCoolingCoolingOS
Swiftech MCR120-XP EK Supreme HF Swiftech MCP355 Windows 8 Professional Plus MC 64-Bit 
MonitorMonitorKeyboardPower
LG W2442PA 24" 1080P LG W2442PA 24" 1080P Das Keyboard Model S Professional Silverstone ST45SF-G 450W SFX  
CaseMouseMouse Pad
Compact Splash - Coming April 2013 Mionix Naos 5000 Steelseries 4HD 
View all
  hide details  
Reply
post #3 of 41
8/10/09 at 9:52pm
  • Joined: Mar 2007
  • Location: Anchorage, AK
  • Posts: 17,225
  • Trader Rating: 89
  • Folding Team Rank: 420
  •  
    Name Team Rank Points / Jun Work Units / Jun
    ericeod 420 6,644,301 / 2,365,249 1,251 / 128
       
  • Select All Posts By This User
Be warned when using LLC, especially with 45nm CPUs.

Vdroop is a design feature to ensure safe operation of the CPU. Basically loadline calibration defeats the purpose of vdroop. Besides the vdroop, there is also the voltage offsets (commonly called vdrop) which is the difference between bios set vcore and actual windows vcore.

Here is what is going on:

Anandtech: LLC

Here is the standard vdroop as intended:



Here is with LLC or pencil mod:


Quote:
No Vdroop means the VRM circuit must work harder at maintaining a constant voltage

In this next case we eliminate Vdroop altogether and examine the chaos that ensues. As illustrated by our model, removing Vdroop does nothing to reduce the magnitude of the idle to full-load transient but does increase the settling time as the VRM must recover to a higher final regulation voltage. As in the case of no Voffset, it is possible to exceed the maximum allowable CPU voltage (VID). Clearly, removing Vdroop gains us nothing and only serves to create problems that are more serious.

So what happens when we remove both Voffset and Vdroop? The answer is simple - bad things. Although the difference between the maximum positive and negative peak overshoot are the same, severe violations to the CPU VID limit occur. If you're asking yourself what's the problem with this, consider the case of a CPU VID of 1.60000V - because the user feels this is the absolute maximum CPU voltage that they will allow. Just how high do you think CPU voltage will go after leaving a heavy load condition? We can't be sure without knowing more of the details, but we can certainly conclude that it will be well in excess of 1.6V. If you've ever run a benchmark only to have your system crash right as it finishes then you have experienced the consequences of this poor setup.


Finally, let's take one last real-world look at the consequences of removing Vdroop. ASUS' implementation of this feature, labeled as Load Line Calibration and included with their latest line of motherboards, is particularly worthy of our attention for a number of reasons. The first is that setting lower voltages with this option enabled actually results in a condition in which the CPU voltage under load is higher than the idle voltage. Imagine our confusion as we desperately struggle to understand why our system is Prime95 stable for days yet continues to crash under absolutely no load. What's more, in spite of the absence of droop and for reasons unknown, enabling this feature artificially raises our CPU's minimum stable core voltage at 4.0GHz from 1.28V to about 1.33V. As a result, our system uses more power under load than is otherwise necessary. Our efforts to reduce our processor's supply voltage backfired - instead of lowering the system's total power consumption we managed to affect a 20W increase.
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
post #4 of 41
8/10/09 at 9:52pm
LLC = load line calibration. It reduces your vdroop by slightly increasing the core voltage when a load is placed on the CPU. For overclocking, keep it enabled. Fluctuations in voltage can destablize an overclock. Either that, or your voltage drops too low to sustain a certain overclock - LLC will help that
Needs More Red
(22 items)
  		  
CPUMotherboardGraphicsRAM
i7 3770k Asrock Z77 Extreme4 EVGA GTX 570 4GB G.Skill Ripjaw DDR3-1600 
RAMRAMRAMHard Drive
4GB G.Skill Ripjaw DDR3-1600 4GB Samsung DDR3-1600 Low Voltage 4GB Samsung DDR3-1600 Low Voltage 1TB Samsung F3 
Hard DriveHard DriveOptical DriveOptical Drive
2TB Samsung F4 OCZ Agility 3 256GB Samsung 24x DVD+-RW Lite-On 12x Bluray Burner 
CoolingOSMonitorPower
Coolermaster Hyper 212 EVO Windows 7 Pro x64 Yamakasi Catleap Q270 Antec TruePower 650W 
CaseMouseMouse PadAudio
Thermaltake V4 Black Razer Imperator 4G Steelseries QCK Ultrasone Pro 900 
Audio
Fiio E17 
View all
  hide details  
Reply
Needs More Red
(22 items)
  		  
CPUMotherboardGraphicsRAM
i7 3770k Asrock Z77 Extreme4 EVGA GTX 570 4GB G.Skill Ripjaw DDR3-1600 
RAMRAMRAMHard Drive
4GB G.Skill Ripjaw DDR3-1600 4GB Samsung DDR3-1600 Low Voltage 4GB Samsung DDR3-1600 Low Voltage 1TB Samsung F3 
Hard DriveHard DriveOptical DriveOptical Drive
2TB Samsung F4 OCZ Agility 3 256GB Samsung 24x DVD+-RW Lite-On 12x Bluray Burner 
CoolingOSMonitorPower
Coolermaster Hyper 212 EVO Windows 7 Pro x64 Yamakasi Catleap Q270 Antec TruePower 650W 
CaseMouseMouse PadAudio
Thermaltake V4 Black Razer Imperator 4G Steelseries QCK Ultrasone Pro 900 
Audio
Fiio E17 
View all
  hide details  
Reply
post #5 of 41
8/10/09 at 9:53pm
load line calibration (LLC) is used to stabilize your vcore while under full load. This feature breaks Intel Specification for a specially designed circuit called 'vdroop.' What vdroop does is lowers vcore while under load to prevent voltage irregularities and spikes. Overclockers are concerned with Load Line Calibration since, when enabled, can greatly stabilize an overclock. Without it, LLC will throttle vcore under load and cause system instability.
Dell Optiplex 745
(10 items)
  		  
CPUMotherboardGraphicsRAM
Q6600 (incoming) Dell proprietary Intel Q965 Express Chipset XFX HD 5770 (incoming) 4GB Patriot DDR2 800 
Hard DriveOptical DriveCoolingOS
Hitachi Deskstar 160GB 7200RPM DVDRW Stock Windows XP 32 (for the time being) 
MonitorPower
Dell 22" 1680x1050 Corsair CX430 
View all
  hide details  
Reply
Dell Optiplex 745
(10 items)
  		  
CPUMotherboardGraphicsRAM
Q6600 (incoming) Dell proprietary Intel Q965 Express Chipset XFX HD 5770 (incoming) 4GB Patriot DDR2 800 
Hard DriveOptical DriveCoolingOS
Hitachi Deskstar 160GB 7200RPM DVDRW Stock Windows XP 32 (for the time being) 
MonitorPower
Dell 22" 1680x1050 Corsair CX430 
View all
  hide details  
Reply
post #6 of 41
8/10/09 at 9:56pm
  • Joined: Mar 2007
  • Location: Anchorage, AK
  • Posts: 17,225
  • Trader Rating: 89
  • Folding Team Rank: 420
  •  
    Name Team Rank Points / Jun Work Units / Jun
    ericeod 420 6,644,301 / 2,365,249 1,251 / 128
       
  • Select All Posts By This User
Quote:
Originally Posted by jam3s View Post
load line calibration (LLC) is used to stabilize your vcore while under full load. This feature breaks Intel Specification for a specially designed circuit called 'vdroop.' What vdroop does is lowers vcore while under load to prevent voltage irregularities and spikes. Overclockers are concerned with Load Line Calibration since, when enabled, can greatly stabilize an overclock. Without it, LLC will throttle vcore under load and cause system instability.
It is not so black and white. Vdroop does not cause an unstable OC. Sure with LLC enabled, you can reach a slightly higher OC, but at a price. Vdroop just drops the vcore when the CPU is under load. As explained in my previous post (but with more wording), vdroop protects the CPU from dangerous voltages spikes which can be damaging to a 45nm core. So when you enable LLC (eliminating the vdroop) those voltage spike can reach dangerously high levels. Use it at your own disgression. I highy discourage it's use with a maxed out vcore.
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
post #7 of 41
8/10/09 at 9:56pm
for 45nms it is advisable to disable LLC. I read that also from anandtech.
Tropical Beaver
(13 items)
  		  
CPUMotherboardGraphicsRAM
Intel e7200 @ 3.8Ghz lapped @1.32v ASUS P5Q GeCube HD3850 OC edition OCZ Platinum 1066 4GB 
Hard DriveOptical DriveOSMonitor
400Gb total Samsung Litescribe Win 7 Ultimate x64 Samsung 740N 
KeyboardPowerCaseMouse
A4tech FSP Bluestorm II Trendsonic Wizard Logitech MX518 
Mouse Pad
Nano 
View all
  hide details  
Reply
Tropical Beaver
(13 items)
  		  
CPUMotherboardGraphicsRAM
Intel e7200 @ 3.8Ghz lapped @1.32v ASUS P5Q GeCube HD3850 OC edition OCZ Platinum 1066 4GB 
Hard DriveOptical DriveOSMonitor
400Gb total Samsung Litescribe Win 7 Ultimate x64 Samsung 740N 
KeyboardPowerCaseMouse
A4tech FSP Bluestorm II Trendsonic Wizard Logitech MX518 
Mouse Pad
Nano 
View all
  hide details  
Reply
post #8 of 41
8/10/09 at 10:00pm
Thread Starter 
What is vdroop? Isn't it better to have more vdrop than to let it be reduced and having increased voltage instead? And why is it bad for 45nms? Well I don't overclock.. But for stock, would I need it at load? And it is enabled from bios right? Thanks.
My System
(13 items)
  		  
CPUMotherboardGraphicsRAM
q9550 GIGABYTE GA-EP45-UD3R LGA 775 Intel P45 ATX Intel XFX HD 4890 4gb corsair dual channel 800mhz 
Hard DriveOptical DriveOSMonitor
Western Digital Caviar Black Pioneer DVR-2910 Windows 7 Ultimate Samsung SyncMaster P2350 
PowerCase
corsair 650TX NZXT TEMPEST Crafted Series CS-NT-TEM-B Black Stee 
  hide details  
Reply
My System
(13 items)
  		  
CPUMotherboardGraphicsRAM
q9550 GIGABYTE GA-EP45-UD3R LGA 775 Intel P45 ATX Intel XFX HD 4890 4gb corsair dual channel 800mhz 
Hard DriveOptical DriveOSMonitor
Western Digital Caviar Black Pioneer DVR-2910 Windows 7 Ultimate Samsung SyncMaster P2350 
PowerCase
corsair 650TX NZXT TEMPEST Crafted Series CS-NT-TEM-B Black Stee 
  hide details  
Reply
post #9 of 41
8/10/09 at 10:03pm
the overshoot might kill your chip if it's 45nm and near maximum specified voltage
X13
(13 items)
  		  
CPUMotherboardGraphicsRAM
E8400 C0 P5K-SE/EPU 9800GX2 2X2GB DDR2 Patriot 
Hard DriveOptical DriveOSMonitor
500.1GB Seagate 7200.10 Asus DRW2014-L1T Windows 7 Ultimate x64 Samsung T190 
PowerCase
Coolermaster M520 CM 690 
View all
  hide details  
Reply
X13
(13 items)
  		  
CPUMotherboardGraphicsRAM
E8400 C0 P5K-SE/EPU 9800GX2 2X2GB DDR2 Patriot 
Hard DriveOptical DriveOSMonitor
500.1GB Seagate 7200.10 Asus DRW2014-L1T Windows 7 Ultimate x64 Samsung T190 
PowerCase
Coolermaster M520 CM 690 
View all
  hide details  
Reply
post #10 of 41
8/10/09 at 10:03pm
  • Joined: Mar 2007
  • Location: Anchorage, AK
  • Posts: 17,225
  • Trader Rating: 89
  • Folding Team Rank: 420
  •  
    Name Team Rank Points / Jun Work Units / Jun
    ericeod 420 6,644,301 / 2,365,249 1,251 / 128
       
  • Select All Posts By This User
Quote:
Originally Posted by gera229 View Post
What is vdroop? Isn't it better to have more vdrop than to let it be reduced and having increased voltage instead? And why is it bad for 45nms? Well I don't overclock.. But for stock, would I need it at load? And it is enabled from bios right? Thanks.
vdrop and vdroop are 2 different things (but often confused with each other). Vdrop is the term that describes the CPU voltage difference from what is set in bios and what the system actually uses when the OS loads. Vdroop is the voltage drop you see to the CPU when it is placed under load.

It is bad for 45nm CPUs because of their die shrink, and the fact that their tollerance for voltage is significantly less then their predecessors (65nm).
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
My System
(18 items)
  		  
CPUMotherboardGraphicsRAM
i7 3930k ASUS P9X79 Deluxe ASUS 7970 DC2T 32Gb G.Skill Sniper 1866 Cas10 
Hard DriveHard DriveHard DriveHard Drive
OS: Mushkin Cronos DX SSD Intel X25-M SSD Seagate HHD Samsung F3 
Optical DriveCoolingOSMonitor
LG BluRay x12 Noctua NH-D14 Windows 8 Pro 64 ASUS VW226H 26" x3 Eyefinity 
KeyboardPowerCaseMouse
Logitech G19 Seasonic 1250w 80+ Gold Silverstone Fortress FT02 Logitech G9X 
Audio
ASUS Xonar DX 
View all
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Intel CPUs
Overclock.net › Forums › Intel › Intel CPUs › Cpu llc?