Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor Review


Test Rig:
Intel i7 920 Nehalem
Gigabyte X58-UD4P motherboard
Kingston HyperX DDR3-2000 3GB triple channel kit
Sapphire Radeon HD 4870 Toxic VaporX video card
OCZ EliteXStream 850 Watt power supply
Noctua NH-U12P CPU Cooler (with i7 installation kit)
NZXT Tempest extended midtower
Windows Vista Ultimate 64-bit

As with all CPUs, installation involves proper placement of the processor into the socket. Rather than the two on the LGA 775, there are five “keys” on the LGA 1366, which makes it even more difficult than the earlier CPU to incorrectly place it into the socket. Prepare the CPU heatspreader surface by cleaning it with a lint-free cloth and isopropyl alcohol. Apply thermal compound per the manufacturer’s instructions.

Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor

The LGA 1366 CPU cooler placement is similar to the LGA 775, except that the holes are farther apart. So be aware, a cooler designed for the Core 2 will not fit the i7 as is. I assume that some companies are coming out with adapter kits, I know that Noctua has produced a kit that will convert all of their coolers for use with LGA 1366. I recently reviewed a CoolIT liquid cooler that had an adapter for the i7.

As far as the traditional LGA 775 push pins, I did not receive a stock cooler with this i7, so I don’t know if Intel still uses the same push pins.

BIOS are different for every motherboard, so I won’t be covering specific BIOS settings here, they will be covered in the upcoming motherboard review. But I will touch on some of the BIOS information.

The i7 920 runs at 2.66gHz, a result of a 133 Base Clock (BCLK) Frequency and a 20x multiplier. The QPI Link Speed is 4.8gHz. This particular processor is maxed at 20x, but multipliers between 12x and 20x are available. Overclocking is performed by raising the BLCK.

Just to note, when Enhanced Intel SpeedStep in disabled in the BIOS, but Intel Turbo Boost is enabled, the CPU is clocked at 2.798gHz. Add the 133mHz boost to the 2.66gHz stock clock, and there you have it.

Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor

Of course ya gotta try it. I had no idea whatsoever what kind of overclock I might get from the i7 920, but I always had pretty good luck with both of my E8400s and Q6600. My cooler kept a steady 27C at idle, so I felt pretty comfortable trying a healthy overclock.

I started out by disabling all of Intel’s energy-saving functions, and Intel Turbo Boost to eliminate possible problems there. I changed the QPI Link Speed to x36 and BCLK to 200. Yes, I started out trying for a 4.0gHz overclock. This boosted the QPI to 7.2gHz, a pretty significant jump, and ran the memory at DDR3-1600. I decided not to fool with the memory speed, maybe later. The “Uncore”, which is the speed of the L3 cache and memory controller should be twice the memory speed, so I set it at 3.2gHz. With both memory and Uncore well under their limits, I felt that any problems should be limited to the processor. Finally I set the Vcore at 1.425, and the QPI/VTT voltage to 1.5125, hoping my cooler would make the trip.

First try, I made it to just before the Welcome screen, and got a BSOD. Went back to the BIOS, and enabled the Load Line Calibration, and hit paydirt. 4.0 Gigs! Guys, that is a 50.4% overclock. On air!

Intel Core i7 920 Nehalem 2.66GHz LGA 1366 Processor