BACKGROUND - Intel introduced a new generation of processors for PCs and laptops codenamed Haswell earlier this year. The fourth-generation Core processors are very similar to its predecessor Ivy Bridge, but it features a new architecture that allows for even higher efficiency.
1. You need a new motherboard
For now, the new processor is only available in the Core i5 and i7 flavors. And unsurprisingly, the model numbers start with a 4. In line with Intel's strategy, this fourth generation (after the 'tick' of Ivy Bridge) is a 'tock': that means it introduces a brand new architecture on the same production process as its predecessor.
Like the Ivy Bridge models, Haswell processors use 22 nm Tri-Gate '3D' transistors. Haswell processors do require a new socket (called LGA 1150) and thus a new motherboard.
The most important innovations for the CPU architecture are the support for new instructions (AVX 2) and transactional memory (TSX or Intel abbreviation). TSX can make multi-threaded software work a lot faster. Software must be optimized, so it remains to be seen what the profit will be in practice. By the way, not all Haswell CPUs include support for TSX.
Furthermore, Intel continues to integrate chipset functionality into the processor. After the integration of the memory controller at 'Nehalem' and the PCI Express controller at 'Sandy Bridge', an integrated voltage controller now follows. For ultrabooks and all-in-one PCs, there will even be a complete system-on-a-chip (SoC) variant of the processor, in which the CPU and chipset are combined in a so-called multi-chip package.
Haswell is Intel's code name for the fourth-generation Core processors.
2. Haswell is much stronger graphically
The integrated graphics chip (or GPU) has become considerably faster in Haswell and now has support for DirectX 11.1. Intel comes with different variants: with 6 GPU cores (GT1), 20 GPU cores (GT2) and even 40 GPU cores (GT3). Haswell processors with this GT3 variant even come with 128 MB graphics memory baked into the CPU (eDRAM in jargon), which further increases performance.
However, that GT3 version will only end up in laptops and all-in-one PCs. Intel will call the GT1 and GT2 variants HD Graphics as usual. A new brand name is used for the GT3 and GT3e: Iris Graphics and Iris Pro Graphics. With this, Intel indicates that it is now entering direct competition with GeForce and Radeon GPUs for the laptop.
We can clearly distinguish the four processor cores and the graphics core (right).
3. Haswell is for desktops and laptops
Intel has released fifteen Haswell processors for desktops, all in the Core i5 and Core i7 class. The top model and successor to the Core i7-3770K is the Core i7-4770K. It contains four cores with HyperThreading, with a clock speed of 3.5 GHz and a maximum turbo of 3.9 GHz. The Core i5-4670K succeeds the Core i5-3570K. Again, the main difference between the i7s and i5s is the lack of HyperThreading on the and a smaller cache on the i5.
The large number of models at introduction is partly explained by the many variants with different consumption indications or TDP (Thermal Design Power). In theory, the fastest models consume slightly more than the Ivy Bridge predecessors and have a TDP of 85 watts.
Intel also has variants with a TDP of 65 W (recognizable by the -S in the type number), 45 W (-T) and 35 W (-T). These variants have somewhat lower clock frequencies, especially the basic frequency is lower.
At launch, Intel had only a few mobile Haswell processors, all of which fall in the most expensive Core i7 range. However, it already reported that at least thirteen new models should be released this year. A special feature of the mobile Haswell processors is the S0ix sleep mode, which allows synchronization with web services without actually waking the processor (and notebook).
The top models in the Core i5 and i7 series are marketed first.
4. Slight speed gain
We have extensively tested the new Haswell processors and compared them with virtually all processors currently available. The test shows that the CPU performance has increased by about 7 percent compared to the previous generation. For example, in the Cinebench 11.5 benchmark, Ivy Bridge's top model i7-3770K achieves a score of 7.58 points, while the Core i7-4770K comes in at 8.08 points. That is a bit disappointing for a completely new architecture.
The improvements in the graphical area are (much) greater, we see an average gain of 50 percent. Another big improvement is that the average power consumption has decreased considerably both in idle mode and under load. Even the top models with a higher TDP than the Ivy Bridge counterparts turn out to be more economical in practice, although this is largely explained by the new chipsets (8 series). They are built with much more modern 32nm transistors than the 7 series, which still used a 65nm process.
In that light, the small speed increase of the CPU itself is more palatable, all the more if we consider that the market today revolves around mobile devices. Higher desktop performance is less important: there are already few mainstream applications that can fully utilize the enormous computing power of a modern processor.
Chipsets with bug: 8 series
With a new generation of processors come new chipsets. The 7-series is followed by the 8-series, which has the same variants. So we see a Z87, Z85, Q87, Q85 and a B85.
The differences between them are as we knew them from the Z77 line. The biggest improvement of the new generation is support for more SATA 6Gbit/s and USB3.0 connections, as well as lower power consumption.
A usb3.0 bug is present in the current version of the chipsets. This ensures that a connected device can be temporarily disconnected when a system wakes up from sleep mode. Open files on those devices therefore have to be opened again in certain cases (which does not lead to data loss).
This bug only occurs in combination with certain USB chips and will be fixed with a new C2 revision at the end of July, according to Intel. The bug-free motherboards, systems and laptops will be available around the fall.
Conclusion
Haswell, or fourth-generation Intel Core processors, doesn't bring the dramatic performance boost to the desktop that we usually associate with a new Intel architecture. Instead, the focus has been on further reducing power consumption and implementing techniques whose benefits will only become apparent in future software.
Haswell is a significant advance, especially for mobile processors, and it is expected that the differences between laptops will be much greater, both in terms of graphics performance and battery life.
