Haswell CPU / GPU / Overclocking

Compared to Ivy Bridge the new Haswell processors are once again a bit more complex. Meanwhile those processors weigh 1.4 billion transistors. When Intel launched their Ivy Bridge processors, most of the changes went into the integrated graphics part of the CPU. With the new Haswell processors thing are quite similar. Intel did a lot of changes regarding the IGP part once again, to try catch up with AMD as soon as possible. Taking a closer look at the number of execution units shows that Intel provides the HD 4600 with 20, whereas the HD 4000, which can be found in the Core i7-3770K CPUs, only features 16 of them. When you look at the HD5200 IGP, which is the most high-end part, that comes with the Core i7-4770R CPU, then you'll even find 40 execution units and right next to them, on die, there is an additional eDRAM cache.

Furthermore Intel improved the power regulation within the new Haswell processors. In this regard there are quite a few new things worth mentioning. Haswell features an internal voltage regulation circuitry. Instead of several input voltages, which had been handled by an external power design (located on the motherboard), there are now only two input voltages required to be delivered by the onboard power design. One of these voltages is called the Vccin, which is providing the core logic with power and the other is called the Vddq, which is basically the DRAM voltage. Vccin can vary between 1.8 and 2.3 and the maximum is 3.04 Volt. Vddq depends on the memory used in the system.

Taking a closer look at Intels Z87 chipset, which carries the new socket LGA1150, we find a few very reasonable changes, when comparing with the predecessor. For example, Intel finally provides more than just two SATA 6Gbps ports. Nowadays you can find six SATA 6Gbps ports provided by the Z87 PCH. Furthermore up to six USB 3.0 and up to 14 USB 2.0 ports can be wired to the Z87 chipset. Furthermore the integrated graphics unit is able to drive up to three displays simultaneously. Wired directly to the CPU there are 16 PCI Express 3.0 lanes, which can be driven in a x16, x8/x8 or an x8/x4/x4 configuration.

To make sure that the memory subsystem is not going to become the bottleneck, there is a dual channel DDR3 1600 MHz interface. During our tests we found out that most of the new chips are perfectly capable of handling memory with 3'000 MHz frequency, which is quite an improvement over the previous generation.

Overclocking

With the new Haswell CPUs there are also some news regarding overclocking. Intel decided to increase the max multiplyer to 80. Furthermore there are now presets for the bus clock, which means, that you can set 100 MHz, 125 MHz as well as 166 MHz. The basic principle is identical to the X79 Platform. Furthermore there should be a +/- 7 percent range within which the busclock can be changed from the presets. Never the less, already weeks before the launch there were validations, showing Haswell systems running at 200 MHz BCLK. Another thing that happens when you change the BCLK presets is that the max multiplyers come down. In case of 100 MHz max multiplyer is x80, selecting 125 MHz reduces max multiplyer to x64 and setting 166 MHz gives you a max multiplyer of x48.

Page 1 - Introduction	Page 9 - SuperPi / WPrime
Page 2 - Specifications	Page 10 - WinRar
Page 3 - Ivy Bridge CPU / Chipset / Overclocking	Page 11 - Crysis
Page 4 - Test Setup	Page 12 - Resident Evil 5
Page 5 - Futuremark	Page 13 - Street Fighter 4
Page 6 - Cinebench	Page 14 - Power consumption
Page 7 - SiSoft Sandra 1	Page 15 - Conclusion
Page 8 - SiSoft Sandra 2

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