Intel Core i7-4578U vs Intel Core i7-4940MX
Intel Core i7-4578U► remove from comparison
The Intel Core i7-4578U is a LV (low voltage) dual-core processor for large ultrabooks launched in Q3/2014. It is based on the Haswell architecture and is manufactured in 22nm. Due to Hyper-Threading, the two cores can handle up to four 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 3.5 GHz.
The performance of the Core i7-4578U is slightly above the older and somewhat higher clocked Core i7-3540M. However, when using new instruction sets such as AVX2 the performance can be significantly better. Thus, the CPU has sufficient power for office and multimedia purposes as well as more demanding applications.
The integrated Iris Graphics 5100 offers 40 Execution Units (EUs) clocked at 200 - 1200 MHz with Turbo Boost, making it significantly faster than the HD Graphics 4000. As a result, the Iris Graphics competes with dedicated lower mid-range graphics cards (e.g. GeForce GT 720M).
The i7-4578U is rated at a TDP of 28 W including the graphics card, memory controller, VRMs and the integrated chipset. Therefore, the CPU is suited for larger, well-cooled ultrabooks.
Intel Core i7-4940MX► remove from comparison
The Intel Core i7-4940MX is a high-end quad-core processor for laptops and successor of the i7-4930MX. It is based on the Haswell architecture and was launched in Q1/2014. 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 3.1 GHz but can dynamically increase clock rates with Turbo Boost up to 3.8 GHz (for 4 active cores), 3.9 GHz (for 2 active cores) and 4.0 GHz (for 1 active core). Furthermore, the Extreme CPUs offer an unlocked multiplicator for easy overclocking.
Haswell is the successor to the Ivy Bridge architecture with improvements on both GPU and CPU performance. The CPUs are produced in 22nm and offer an optimized branch prediction as well as additional execution ports, increasing the performance per clock by about 5 - 10 percent. Furthermore, new features like AVX2 and FMA should increase the performance in future applications.
Compared to the Core i7-4930MX, the 4940MX is clocked just 100 MHz higher and therefore only slightly faster. Overall, the performance is similar to the Desktop Core i7-4770K. Even extremly demanding software or multitasking will be handled easily.
The integrated Intel HD Graphics 4600 offers 20 Execution Units (EUs) clocked at 400 MHz up to 1350 MHz with Turbo Boost, making it about 30 % faster than the HD 4000. This is slightly slower than the AMD Radeon HD 8650G, but similar to a dedicated GeForce GT 720M.
The i7-4940MX is rated at a TDP of 57 W including graphics card, memory controller and VRMs. Therefore, the CPU is only suited for laptops 17-inches or greater.
|Model||Intel Core i7-4578U||Intel Core i7-4940MX|
|Series||Intel Core i7||Intel Core i7|
|Series: Core i7 Haswell|
|Clock||3000 - 3500 MHz||3100 - 4000 MHz|
|L1 Cache||128 KB||256 KB|
|L2 Cache||512 KB||1 MB|
|L3 Cache||4 MB||8 MB|
|Cores / Threads||2 / 4||4 / 8|
|TDP||28 Watt||57 Watt|
|Transistors||1300 Million||1400 Million|
|Technology||22 nm||22 nm|
|Die Size||181 mm2||177 mm2|
|max. Temp.||100 °C||100 °C|
|Features||Iris Graphics 5100 (200 - 1200 MHz), DDR3(L)-1600 Memory Controller, HyperThreading, AVX, AVX2, Quick Sync, Virtualization, AES-NI||HD Graphics 4600 (400 - 1350 MHz), DDR3(L)-1600 Memory Controller, HyperThreading, AVX, AVX2, Quick Sync, Virtualization, vPro, AES-NI|
|iGPU||Intel Iris Graphics 5100 (200 - 1200 MHz)||Intel HD Graphics 4600 (400 - 1350 MHz)|
|$426 U.S.||$1096 U.S.|
|Manufacturer||Intel Core i7 4578U||Intel Core i7 4940MX|