The Best Memory for Sandy Bridge

Test Seup

Intel 'Sandy Bridge'

• Intel Core i7-2600K - 4(8) - Hyperthreading Enabled, TurboBoost and C1E Disabled.
  
• Gigabyte GA-P67A-UD4 - (Intel P67 F5r BIOS)
  
• 4GB G.Skill Perfect Storm 2,200MHz CL8

Intel 'Lynnfield

• Intel Core i7-860 - 4(8) - Hyperthreading Enabled, TurboBoost and C1E Disabled.
  
• Asus P7P55 Deluxe - (Intel P55 1901 BIOS)
  
• 4GB G.Skill Perfect Storm 2,200MHz CL8

Intel 'Nehalem'

• Intel Core i7-940 - 4(8) - Hyperthreading Enabled, TurboBoost and C1E Disabled.
  
• Gigabyte GA-X58A-UD7 - (Intel X58/ICH10R FB BIOS)
  
• 6GB Corsair Dominator 1,600MHz CL8

Common Components

• MSI GeForce GTX 480 Lightning Graphics Card
  
• GeForce Driver Version 260.66
  
• Crucial RealSSD C300 128GB
  
• 650W Seasonic X-series PSU
  
• Microsoft 7 Home Premium x64

Memory Speeds Tested

Intel Sandy Bridge

• (3,000MHz CPU) 100MHz x 30: 1,333MHz - 9-9-9-24-1T
  
• (3,000MHz CPU) 100MHz x 30: 1,600MHz - 9-9-9-24-1T
  
• (3,000MHz CPU) 100MHz x 30: 1,866MHz - 9-9-9-24-1T
  
• (3,000MHz CPU) 100MHz x 30: 2,133MHz - 9-9-9-24-1T

Intel Lynnfield

• (2,992MHz CPU / 2,448MHz CPU Uncore) 136MHz x 22: 1,360MHz - 9-9-9-24-1T
  
• (2,992MHz CPU / 2,448MHz CPU Uncore) 136MHz x 22: 1,632MHz - 9-9-9-24-1T
  
• (3,002MHz CPU / 2,844MHz CPU Uncore) 158MHz x 19: 1,896MHz - 9-9-9-24-1T
  
• (3,009MHz CPU / 3,186MHz CPU Uncore) 177MHz x 17: 2,124MHz - 9-9-9-24-1T

Intel Nehalem

• (2,992MHz CPU / 2,720MHz CPU Uncore) 136MHz x 22: 1,360MHz - 9-9-9-24-1T
  
• (2,992MHz CPU / 3,264MHz CPU Uncore) 136MHz x 22: 1,632MHz - 9-9-9-24-1T

We tried to keep the CPU frequencies as consistently close to 3GHz as possible, even if this meant not running the memory at exactly the same frequencies. This is because the memory gaps were far larger, so small changes had less effect versus CPU frequency.

We found that our Core i7-940 couldn't use a memory frequency above 1,600MHz, because at 1,866MHz it required a 3.7GHz CPU Uncore, which was beyond its scope. The more recent 32nm Intel Core i7-980X Extreme Edition only requires a 1.5x CPU:Uncore ratio, which enables higher memory speeds. However, even with two cores disabled, its 12MB of L3 cache would have given it a performance advantage over the other CPUs and their 8MB of L3 cache.