i7-1255U vs Xeon E5520
Aggregate performance score
Core i7-1255U outperforms Xeon E5520 by a whopping 436% based on our aggregate benchmark results.
Primary details
Comparing Xeon E5520 and Core i7-1255U processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2110 | 896 |
| Place by popularity | not in top-100 | 74 |
| Cost-effectiveness evaluation | 2.58 | no data |
| Market segment | Server | Laptop |
| Series | no data | Intel Alder Lake-M |
| Power efficiency | 1.88 | 53.82 |
| Architecture codename | Gainestown (2009−2010) | Alder Lake-U (2022) |
| Release date | 30 March 2009 (15 years ago) | 23 February 2022 (2 years ago) |
| Launch price (MSRP) | $19 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Xeon E5520 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 | 4 (Quad-Core) | 10 (Deca-Core) |
| Threads | 8 | 12 |
| Base clock speed | 2.26 GHz | 1.7 GHz |
| Boost clock speed | 2.53 GHz | 4.7 GHz |
| L1 cache | 64 KB (per core) | 80K (per core) |
| L2 cache | 256 KB (per core) | 1.25 MB (per core) |
| L3 cache | 8 MB (shared) | 12 MB (shared) |
| Chip lithography | 45 nm | 10 nm |
| Die size | 263 mm2 | no data |
| Maximum core temperature | 72 °C | 100 °C |
| Number of transistors | 731 million | no data |
| 64 bit support | + | + |
| Windows 11 compatibility | - | + |
Compatibility
Information on Xeon E5520 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 | 2 | 1 |
| Socket | FCLGA1366 | Intel BGA 1744 |
| Power consumption (TDP) | 80 Watt | 15 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Xeon E5520 and Core i7-1255U. You'll probably need this information if you require some particular technology.
| AES-NI | - | + |
| FMA | - | + |
| AVX | - | + |
| Enhanced SpeedStep (EIST) | + | + |
| Turbo Boost Technology | 1.0 | no data |
| Hyper-Threading Technology | + | no data |
| TSX | - | + |
| Idle States | + | no data |
| Demand Based Switching | + | no data |
| PAE | 40 Bit | no data |
Security technologies
Xeon E5520 and Core i7-1255U technologies aimed at improving security, for example, by protecting against hacks.
| TXT | + | + |
| EDB | + | no data |
Virtualization technologies
Virtual machine speed-up technologies supported by Xeon E5520 and Core i7-1255U are enumerated here.
| VT-d | + | + |
| VT-x | + | + |
| EPT | + | no data |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Xeon E5520 and Core i7-1255U. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR4, DDR5 |
| Maximum memory size | 144 GB | no data |
| Max memory channels | 3 | no data |
| Maximum memory bandwidth | 25.6 GB/s | no data |
| ECC memory support | + | - |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | N/A | Intel Iris Xe Graphics G7 96EUs ( - 1250 MHz) |
Peripherals
Specifications and connection of peripherals supported by Xeon E5520 and Core i7-1255U.
| PCIe version | 2.0 | 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.
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.
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
| Performance score | 1.59 | 8.53 |
| Recency | 30 March 2009 | 23 February 2022 |
| Physical cores | 4 | 10 |
| Threads | 8 | 12 |
| Chip lithography | 45 nm | 10 nm |
| Power consumption (TDP) | 80 Watt | 15 Watt |
i7-1255U has a 436.5% higher aggregate performance score, an age advantage of 12 years, 150% more physical cores and 50% more threads, a 350% more advanced lithography process, and 433.3% lower power consumption.
The Core i7-1255U is our recommended choice as it beats the Xeon E5520 in performance tests.
Be aware that Xeon E5520 is a server/workstation processor while Core i7-1255U is a notebook one.
Should you still have questions on choice between Xeon E5520 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.
