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Intel Core i7-3940XM vs Intel Core i7-820QM

Intel Core i7-3940XM

► remove from comparison Intel 3940XM

The Intel Core i7-3940XM is the fastest quad-core processor for laptops (at the time of introduction in September 2012) an successor of the i7-3920XM. Due to Hyperthreading, the four cores can handle up to eight threads in parallel leading to better utilization of the CPU. Each core offers a base speed of 3.0 GHz but can dynamically increase clock rates with Turbo Boost up to 3.7 GHz (for 4 active cores), 3.8 GHz (for 2 active cores) and 3.9 GHz (for 1 active core). Furthermore, the Extreme CPUs offer an unlocked multiplicator for easy overclocking.

Ivy Bridge is an enhanced die shrink of the Sandy Bridge architecture with improvements on both GPU and CPU performance. The CPUs are produced in 22nm (versus 32nm Sandy Bridge CPUs) and are the first to introduce 3D transistors for increased energy efficiency when compared to similarly clocked Sandy Bridge processors. Other new features are integrated PCI Express 3.0 and  DDR3(L)-1600 support.

The performance of the Core i7-3940XM should be slightly above a similarly clocked Sandy Bridge processor due to slight architectural improvements. Because of the higher clock speed, the former champion Core i7-3920XM should be outperformed by about 3%.

The integrated Intel HD Graphics 4000 offers 16 Execution Units (EUs) clocked at 650 MHz up to 1350 MHz with Turbo Boost, making it the fastest variant.

The XM CPUs are rated at a TDP of 55 Watts including graphics card and memory controller and therefore 10 Watt higher than the other quad-core models.  Therefore, the CPU is well-suited for laptops 17-inches or greater.

Intel Core i7-820QM

► remove from comparison Intel 820QM

The Intel Core i7 820QM is a high end quad core CPU in 2009. It features 4 cores (quad core CPU) and Hyperthreading. Therefore, 8 threads can be worked on simultaneously.

Because of the Turbo Mode, the CPU is clocked with up to 3.06 GHz and therefore can perform very well in single core applications like older games.

The Core i7 line has an integrated memory controller for DDR3 bars (1066 or 1333). Therefore, the memory performance is very good (compared to older CPUs with external memory controllers). Still, this also leads to the higher TDP of the whole chip.

The Core micro-architecture is still very similar to the one used in the Core 2 CPUs, therefore the performance per MHz (neglecting the integrated memory controller, hyperthreading and Turbo Boost) is similar.

The power consumption of up to 45 Watt (TDP) is quite high for a laptop CPU and because of the Turbo Mode, the power consumption should reach these high values. Therefore, the CPU is only suited for large laptops.

 

ModelIntel Core i7-3940XMIntel Core i7-820QM
CodenameIvy BridgeClarksfield
SeriesIntel Core i7Intel Core i7
Series: Core i7 Clarksfield
Intel Core i7-3940XM « 3 - 3.9 GHz4 / 8 cores8 MB L3
Intel Core i7-3920XM compare2.9 - 3.8 GHz4 / 8 cores8 MB L3
Intel Core i7-3840QM compare2.8 - 3.8 GHz4 / 8 cores8 MB L3
Intel Core i7-3820QM compare2.7 - 3.7 GHz4 / 8 cores8 MB L3
Intel Core i7-3740QM compare2.7 - 3.7 GHz4 / 8 cores6 MB L3
Intel Core i7-3720QM compare2.6 - 3.6 GHz4 / 8 cores6 MB L3
Intel Core i7-3635QM compare2.4 - 3.4 GHz4 / 8 cores6 MB L3
Intel Core i7-3630QM compare2.4 - 3.4 GHz4 / 8 cores6 MB L3
Intel Core i7-3615QM compare2.3 - 3.3 GHz4 / 8 cores6 MB L3
Intel Core i7-3610QM compare2.3 - 3.3 GHz4 / 8 cores6 MB L3
Intel Core i7-3632QM compare2.2 - 3.2 GHz4 / 8 cores6 MB L3
Intel Core i7-3612QM compare2.1 - 3.1 GHz4 / 8 cores6 MB L3
Intel Core i7-3540M compare3 - 3.7 GHz2 / 4 cores4 MB L3
Intel Core i7-3520M compare2.9 - 3.6 GHz2 / 4 cores4 MB L3
Intel Core i7-3687U compare2.1 - 3.3 GHz2 / 4 cores4 MB L3
Intel Core i7-3667U compare2 - 3.2 GHz2 / 4 cores4 MB L3
Intel Core i7-3537U compare2 - 3.1 GHz2 / 4 cores4 MB L3
Intel Core i7-3517U compare1.9 - 3 GHz2 / 4 cores4 MB L3
Intel Core i7-3689Y compare1.5 - 2.6 GHz2 / 4 cores4 MB L3
Intel Core i7-940XM compare2.13 - 3.33 GHz4 / 8 cores8 MB L3
Intel Core i7-920XM compare2 - 3.2 GHz4 / 8 cores8 MB L3
Intel Core i7-840QM compare1.86 - 3.2 GHz4 / 8 cores8 MB L3
Intel Core i7-820QM « 1.73 - 3.06 GHz4 / 8 cores8 MB L3
Intel Core i7-740QM compare1.73 - 2.93 GHz4 / 8 cores6 MB L3
Intel Core i7-720QM compare1.6 - 2.8 GHz4 / 8 cores6 MB L3
Clock3000 - 3900 MHz1730 - 3060 MHz
L1 Cache256 KB256 KB
L2 Cache1 MB1 MB
L3 Cache8 MB8 MB
Cores / Threads4 / 84 / 8
TDP55 Watt45 Watt
Transistors1400 Million774 Million
Technology22 nm45 nm
Die Size160 mm2296 mm2
max. Temp.105 °C100 °C
SocketFCPGA988RPGA989
FeaturesHD Graphics 4000, DDR3(L)-1600 Memory Controller, HyperThreading, AVX, Quick Sync, Virtualization
iGPUIntel HD Graphics 4000 (650 - 1350 MHz)
Architecturex86x86
$1096 U.S.$546 U.S.
Announced
FSB2500
Manufacturerark.intel.com

Benchmarks

Cinebench R11.5 - Cinebench R11.5 CPU Multi 64 Bit
min: 7.45     avg: 7.5     median: 7.5 (10%)     max: 7.46 Points
min: 2.95     avg: 3.1     median: 3 (4%)     max: 3.44 Points
Cinebench R11.5 - Cinebench R11.5 CPU Single 64 Bit
100%
1 3940XM +
min: 1.62     avg: 1.6     median: 1.6 (38%)     max: 1.63 Points
Cinebench R10 - Cinebench R10 Rend. Single (32bit)
min: 5246     avg: 5255     median: 5252 (32%)     max: 5267 Points
min: 3075     avg: 3457     median: 3271.5 (20%)     max: 4185 Points
Cinebench R10 - Cinebench R10 Rend. Multi (32bit)
min: 20438     avg: 20582     median: 20564 (15%)     max: 20744 Points
min: 8341     avg: 9174     median: 8559 (6%)     max: 11966 Points
Cinebench R10 - Cinebench R10 Rend. Multi (64bit)
min: 25475     avg: 25600     median: 25624 (16%)     max: 25700 Points
min: 10222     avg: 10498     median: 10317 (7%)     max: 11311 Points
Cinebench R10 - Cinebench R10 Rend. Single (64bit)
min: 6506     avg: 6621     median: 6669 (8%)     max: 6687 Points
min: 3709     avg: 3952     median: 3987 (5%)     max: 4101 Points
wPrime 2.10 - wPrime 2.0 1024m *
min: 208.8     avg: 219.2     median: 215.7 (3%)     max: 233 s
min: 424     avg: 1140     median: 1361.5 (16%)     max: 1412 s
wPrime 2.10 - wPrime 2.0 32m *
min: 6.8     avg: 7     median: 7 (1%)     max: 7.169 s
min: 13.73     avg: 35.2     median: 42 (8%)     max: 43 s
WinRAR - WinRAR 4.0
100%
1 3940XM +
min: 3467     avg: 4124     median: 4123.5 (7%)     max: 4780 Points
X264 HD Benchmark 4.0 - x264 Pass 2
100%
1 3940XM +
40.6 fps (1%)
X264 HD Benchmark 4.0 - x264 Pass 1
100%
1 3940XM +
161.1 fps (4%)
TrueCrypt - TrueCrypt Serpent
100%
1 3940XM +
min: 0.373     avg: 0.4     median: 0.4 (11%)     max: 0.386 GB/s
TrueCrypt - TrueCrypt Twofish
100%
1 3940XM +
min: 0.64     avg: 0.7     median: 0.7 (11%)     max: 0.66 GB/s
TrueCrypt - TrueCrypt AES
100%
1 3940XM +
min: 3.5     avg: 3.6     median: 3.7 (10%)     max: 3.7 GB/s
3DMark 06 - CPU - 3DMark 06 - CPU
min: 7166     avg: 7182     median: 7176 (15%)     max: 7203 Points
min: 3053     avg: 3226     median: 3149 (7%)     max: 3629 Points
Super Pi mod 1.5 XS 1M - Super Pi mod 1.5 XS 1M *
min: 9     avg: 9.2     median: 9 (2%)     max: 9.554 s
14 s (3%)
Super Pi mod 1.5 XS 2M - Super Pi mod 1.5 XS 2M *
min: 21     avg: 21.1     median: 21 (1%)     max: 21.26 s
min: 31     avg: 31.7     median: 32 (1%)     max: 32 s
Super Pi Mod 1.5 XS 32M - Super Pi mod 1.5 XS 32M *
min: 518     avg: 526     median: 525.5 (2%)     max: 533 s
min: 765     avg: 787     median: 780 (3%)     max: 817 s
SiSoft Sandra Dhrystone (MIPS) - SiSoft Sandra Dhrystone (MIPS)
100%
1 3940XM +
min: 147240     avg: 147620     median: 147620 (70%)     max: 148000 MIPS
SiSoft Sandra Whetstone (MFLOPS) - SiSoft Sandra Whetstone (MFLOPS)
100%
1 3940XM +
min: 89600     avg: 89630     median: 89630 (69%)     max: 89660 MFLOPS
PCMark 05 - PCMark 05 - Standard
100%
1 820QM +
7734 Points (16%)
Windows 7 Experience Index - Win7 CPU
7.7 Points (99%)
min: 7.1     avg: 7.2     median: 7.2 (92%)     max: 7.2 Points
3DMark Vantage - 3DM Vant. Perf. CPU no Physx
min: 25344     avg: 25795     median: 25885 (20%)     max: 26157 Points
min: 10851     avg: 11570     median: 11251.5 (9%)     max: 12631 Points
3DMark 11 - 3DM11 Performance Physics
min: 7611     avg: 8737     median: 9032 (22%)     max: 9568 Points
4002 Points (10%)
3DMark - 3DMark Ice Storm Physics
100%
1 3940XM +
48410 Points (39%)
3DMark - 3DMark Cloud Gate Physics
100%
1 3940XM +
7208 Points (18%)
3DMark - 3DMark Fire Strike Standard Physics
100%
1 3940XM +
9863 Points (18%)

Average Benchmarks Intel Core i7-3940XM → 100% n=14

Average Benchmarks Intel Core i7-820QM → 50% n=14

- Range of benchmark values for this graphics card
red legend - Average benchmark values for this graphics card
* Smaller numbers mean a higher performance
1 This benchmark is not used for the average calculation

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v1.34
log 06. 08:23:58

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#13 return log +0.003s ... 0.043s

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> Expert Reviews and News on Laptops, Smartphones and Tech Innovations > Benchmarks / Tech > Processor Comparison - Head 2 Head
Redaktion, 2017-09- 8 (Update: 2023-07- 1)