Intel Haswell review
After more than 18 months of anticipation, the Intel Haswell architecture is finally here. Haswell – officially known as 4th Generation Intel Core – promises to reduce power requirements and boost performance, especially in the arena of graphics.
Ultrabooks using Haswell CPUs must meet new hardware requirements, including a touchscreen, wireless display technology and an idle battery life of at least nine hours. Laptops that don’t meet these requirements can’t use the Ultrabook brand.
Haswell chips are built on the same 22nm process as Ivy Bridge, so the power savings aren’t achieved through miniaturisation. They’re the result of two technical innovations. The first is a new power management framework, which lets the CPU handle device driver events in scheduled batches, rather than in real time, so it can spend more time powered down between bursts of activity. Intel estimates this improvement can cut power consumption on a regular laptop by around 20%.
The second innovation is a structural change. In low-power processors aimed at Ultrabooks and tablets – denoted by model numbers suffixed with U and Y – the chipset has been moved into the CPU package. This reduces the amount of energy wasted as heat, and gives the processor better control over its power budget. Intel says this allows a “20x” increase in battery life, although in reality this applies only to laptops or tablets in standby mode.
When it comes to actually running code, Haswell brings numerous architectural improvements over previous designs. For the technically minded, these include better branch prediction, a larger translation lookaside buffer, improved out-of-order execution capabilities and a doubling of cache bandwidth. The updated AVX2 instruction set brings new functions, too. In theory, this should give fourth-generation processors a performance edge over their Ivy Bridge forebears in almost every application.
So it proves with the first Haswell chip to emerge, the Core i7-4770K. As the name suggests, this is a direct successor to the Ivy Bridge i7-3770K, and like its predecessor, it’s a desktop quad-core chip – supporting eight threads, thanks to Intel’s Hyper-Threading technology – with a base frequency of 3.5GHz and 8MB of L3 cache. It isn’t a drop-in replacement for the old chip, however: Haswell desktop processors use the new LGA 1150 socket and a new 8 Series chipset.
When benchmarked in Windows 7 with 8GB of RAM, this top-of-the-range model scored 1.16 overall, with respective scores of 1.09, 1.22 and 1.17 for responsiveness, media and multitasking. That’s a fair lick faster than the Ivy Bridge Core i7-3770K, which scored 1.06 in an identical configuration, and well ahead of AMD’s most powerful desktop processor, the FX 8350, which scored 0.95.
Stepping up to Windows 8 knocked 10% off the i7-4770K’s responsiveness score, but nonetheless, the system scored a respectable 1.12 overall. It’s reasonable to expect a comparable step up in speed, compared to the previous generation, across all Haswell chips.
Since this particular processor is a “K” model, you can also overclock its Turbo multipliers; we found the chip ran stably using its stock cooler with its maximum Turbo speed turned up from 3.9GHz to 4.4GHz. This allowed the system to achieve an overall score of 1.25, including a stellar 1.36 score in our media test.