Core 2 Quad Q8400 vs Core i7-3940XM

Place in the ranking	1482	2266
Place by popularity	not in top-100	not in top-100
Market segment	Laptop	Desktop processor
Series	Intel Core i7	no data
Power efficiency	6.32	1.30
Architecture codename	Ivy Bridge (2012−2013)	Yorkfield (2007−2009)
Release date	3 September 2012 (12 years ago)	19 April 2009 (15 years ago)
Launch price (MSRP)	$1,096	no data

Detailed specifications

Core i7-3940XM and Core 2 Quad Q8400 basic parameters such as number of cores, number of threads, base frequency and turbo boost clock, lithography, cache size and multiplier lock state. These parameters indirectly say of CPU speed, though for more precise assessment you have to consider their test results.

Physical cores	4 (Quad-Core)	4 (Quad-Core)
Threads	8	4
Base clock speed	3 GHz	2.66 GHz
Boost clock speed	3.9 GHz	0.67 GHz
Bus rate	5 GT/s	1333 MHz
L1 cache	64K (per core)	64 KB (per core)
L2 cache	256K (per core)	4 MB (shared)
L3 cache	8 MB (shared)	0 KB
Chip lithography	22 nm	45 nm
Die size	160 mm²	2x 82 mm²
Maximum core temperature	105 °C	no data
Maximum case temperature (TCase)	no data	71 °C
Number of transistors	1,400 million	456 million
64 bit support	+	+
Windows 11 compatibility	-	-
Unlocked multiplier	+	-
VID voltage range	no data	0.85V-1.3625V

Compatibility

Information on Core i7-3940XM and Core 2 Quad Q8400 compatibility with other computer components: motherboard (look for socket type), power supply unit (look for power consumption) etc. Useful when planning a future computer configuration or upgrading an existing one. Note that power consumption of some processors can well exceed their nominal TDP, even without overclocking. Some can even double their declared thermals given that the motherboard allows to tune the CPU power parameters.

Number of CPUs in a configuration	1	1
Socket	FCPGA988	FCLGA775,LGA775
Power consumption (TDP)	55 Watt	95 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i7-3940XM and Core 2 Quad Q8400. You'll probably need this information if you require some particular technology.

Instruction set extensions	Intel® AVX	no data
AES-NI	+	-
AVX	+	-
Enhanced SpeedStep (EIST)	+	+
My WiFi	+	no data
Turbo Boost Technology	2.0	-
Hyper-Threading Technology	+	-
Idle States	+	+
Thermal Monitoring	+	+
Flex Memory Access	+	no data
Demand Based Switching	-	-
FDI	+	no data
Fast Memory Access	+	no data
FSB parity	no data	-

Security technologies

Core i7-3940XM and Core 2 Quad Q8400 technologies aimed at improving security, for example, by protecting against hacks.

TXT	+	-
EDB	+	+
Identity Protection	+	-
Anti-Theft	+	no data

Virtualization technologies

Virtual machine speed-up technologies supported by Core i7-3940XM and Core 2 Quad Q8400 are enumerated here.

AMD-V	+	-
VT-d	+	no data
VT-x	+	+
EPT	+	no data

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i7-3940XM and Core 2 Quad Q8400. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR3	DDR1, DDR2, DDR3
Maximum memory size	32 GB	no data
Max memory channels	2	no data
Maximum memory bandwidth	25.6 GB/s	no data

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card	Intel HD Graphics 4000	On certain motherboards (Chipset feature)
Quick Sync Video	+	-
Clear Video HD	+	no data
Graphics max frequency	1.35 GHz	no data
InTru 3D	+	no data

Graphics interfaces

Available interfaces and connections of Core i7-3940XM and Core 2 Quad Q8400 integrated GPUs.

Number of displays supported	3	no data
eDP	+	no data
DisplayPort	+	-
HDMI	+	-
SDVO	+	no data
CRT	+	no data

Peripherals

Specifications and connection of peripherals supported by Core i7-3940XM and Core 2 Quad Q8400.

PCIe version	3.0	2.0
PCI Express lanes	16	no data

Synthetic benchmark performance

Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.

Combined synthetic benchmark score

This is our combined benchmark performance rating. We are regularly improving our combining algorithms, but if you find some perceived inconsistencies, feel free to speak up in comments section, we usually fix problems quickly.

i7-3940XM 3.69
+182%

Core 2 Quad Q8400 1.31

Passmark

Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.

i7-3940XM 5840
+183%

Core 2 Quad Q8400 2067

GeekBench 5 Single-Core

GeekBench 5 Single-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses only a single CPU core.

i7-3940XM 641
+95.4%

Core 2 Quad Q8400 328

GeekBench 5 Multi-Core

GeekBench 5 Multi-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses all available CPU cores.

i7-3940XM 2119
+137%

Core 2 Quad Q8400 895

Gaming performance

Pros & cons summary

Performance score	3.69	1.31
Recency	3 September 2012	19 April 2009
Threads	8	4
Chip lithography	22 nm	45 nm
Power consumption (TDP)	55 Watt	95 Watt

i7-3940XM has a 181.7% higher aggregate performance score, an age advantage of 3 years, 100% more threads, a 104.5% more advanced lithography process, and 72.7% lower power consumption.

The Core i7-3940XM is our recommended choice as it beats the Core 2 Quad Q8400 in performance tests.

Be aware that Core i7-3940XM is a notebook processor while Core 2 Quad Q8400 is a desktop one.

Should you still have questions on choice between Core i7-3940XM and Core 2 Quad Q8400, ask them in Comments section, and we shall answer.