Core i7-1255U vs Core 2 Duo E6420
Primary details
Comparing Core 2 Duo E6420 and Core i7-1255U processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | not rated | 878 |
| Place by popularity | not in top-100 | 37 |
| Market segment | Desktop processor | Laptop |
| Series | no data | Intel Alder Lake-M |
| Power efficiency | no data | 53.98 |
| Architecture codename | Conroe (2006−2007) | Alder Lake-U (2022) |
| Release date | April 2007 (17 years ago) | 23 February 2022 (2 years ago) |
Detailed specifications
Core 2 Duo E6420 and Core i7-1255U 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 | 2 (Dual-core) | 10 (Deca-Core) |
| Threads | 2 | 12 |
| Base clock speed | 2.13 GHz | 1.7 GHz |
| Boost clock speed | 2.13 GHz | 4.7 GHz |
| Bus rate | 1066 MHz | no data |
| L1 cache | 64 KB | 80K (per core) |
| L2 cache | 4 MB | 1.25 MB (per core) |
| L3 cache | 0 KB | 12 MB (shared) |
| Chip lithography | 65 nm | Intel 7 nm |
| Die size | 111 mm2 | no data |
| Maximum core temperature | 60 °C | 100 °C |
| Number of transistors | 167 million | no data |
| 64 bit support | + | + |
| Windows 11 compatibility | - | + |
| VID voltage range | 0.85V-1.5V | no data |
Compatibility
Information on Core 2 Duo E6420 and Core i7-1255U 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 | PLGA775 | FCBGA1744 |
| Power consumption (TDP) | 65 Watt | 15 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core 2 Duo E6420 and Core i7-1255U. You'll probably need this information if you require some particular technology.
| Instruction set extensions | no data | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2 |
| AES-NI | - | + |
| FMA | - | + |
| AVX | - | + |
| Enhanced SpeedStep (EIST) | + | + |
| Speed Shift | no data | + |
| Turbo Boost Technology | - | no data |
| Hyper-Threading Technology | - | + |
| TSX | - | + |
| Idle States | + | no data |
| Thermal Monitoring | + | + |
| Flex Memory Access | no data | + |
| Demand Based Switching | - | no data |
| FSB parity | - | no data |
| Deep Learning Boost | - | + |
Security technologies
Core 2 Duo E6420 and Core i7-1255U technologies aimed at improving security, for example, by protecting against hacks.
| TXT | - | + |
| EDB | + | + |
| Secure Key | no data | + |
| OS Guard | no data | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Core 2 Duo E6420 and Core i7-1255U are enumerated here.
| VT-d | no data | + |
| VT-x | + | + |
| EPT | no data | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core 2 Duo E6420 and Core i7-1255U. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR1, DDR2, DDR3 | DDR4, DDR5 |
| Maximum memory size | no data | 64 GB |
| Max memory channels | no data | 2 |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | no data | Intel® Iris® Xe Graphics eligible |
| Quick Sync Video | - | + |
| Graphics max frequency | no data | 1.25 GHz |
| Execution Units | no data | 96 |
Graphics interfaces
Available interfaces and connections of Core 2 Duo E6420 and Core i7-1255U integrated GPUs.
| Number of displays supported | no data | 4 |
Graphics image quality
Maximum display resolutions supported by Core 2 Duo E6420 and Core i7-1255U integrated GPUs, including resolutions over different interfaces.
| Max resolution over HDMI 1.4 | no data | 4096 x 2304 @ 60Hz |
| Max resolution over eDP | no data | 4096 x 2304 @ 120Hz |
| Max resolution over DisplayPort | no data | 7680 x 4320 @ 60Hz |
Graphics API support
APIs supported by Core 2 Duo E6420 and Core i7-1255U integrated GPUs, sometimes API versions are included.
| DirectX | no data | 12.1 |
| OpenGL | no data | 4.6 |
Peripherals
Specifications and connection of peripherals supported by Core 2 Duo E6420 and Core i7-1255U.
| PCIe version | no data | 4.0 |
| PCI Express lanes | no data | 20 |
Synthetic benchmark performance
Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.
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.
Pros & cons summary
| Physical cores | 2 | 10 |
| Threads | 2 | 12 |
| Power consumption (TDP) | 65 Watt | 15 Watt |
i7-1255U has 400% more physical cores and 500% more threads, and 333.3% lower power consumption.
We couldn't decide between Core 2 Duo E6420 and Core i7-1255U. We've got no test results to judge.
Note that Core 2 Duo E6420 is a desktop processor while Core i7-1255U is a notebook one.
Should you still have questions on choice between Core 2 Duo E6420 and Core i7-1255U, ask them in Comments section, and we shall answer.
Similar processor comparisons
We picked several similar comparisons of processors in the same market segment and performance relatively close to those reviewed on this page.
