Core i7-5775C CPU Review

Introduction

We tested the new high-end CPU from the fifth generation Core i processor family: the Core i7-5775C, which has four physical cores (more four logical cores thanks to the Hyper-Threading technology) running at 3.3 GHz with turbo clock up to 3.7 GHz, is manufactured under 14 nm lithography, and comes with the Iris Pro 6200 graphics engine. Let’s see if is it faster than the Core i7-4770K.
The fifth generation of the Intel Core i CPUs is codenamed “Broadwell”, and it is basically a 14nm version of the “Haswell” (fourth generation) processors. It is interesting that most models from this generation are targeted on mobile computers, or SFF (small form factor) desktop computers, like the NUC. There are, until now, only two socketed desktop models, and the speculations are that there will be no more models, since the sixth generation (“Skylake”) models were launched almost simultaneously.
The fifth generation desktop processors launched so far are the Core i5-5675C (four cores, 3.1 GHz, turbo clock up to 3.6 GHz) and the Core i7-5775C (four cores with HT, 3.3 GHz, turbo clock up to 3.7 GHz).
The main difference presented by the “Broadwell” CPUs, compared to the earlier generation ones, besides the 14 nm manufacturing process, is the presence of the Iris Pro 6200 GPU, which supports DirectX 11.2, has 48 execution units (against 20 present on the HD 4600 GPU present in most Haswell processors) and offers a 128 MiB GPU cache (it is listed as an L4 cache in some bibliographies). Besides this, there are some minor optimizations.
We chose to run the tests using a mid/high-end video card, with the integrated video disabled. This is because we assume that the Core i7-5775C, being a high-end desktop CPU, will usually be used with a “real” video card; most users buying a CPU in this price range will use it with a video card. However, we also ran an specific test to discover the integrated video performance.
Figure 1 shows the Core i7-5775C CPU we used in our tests.

Figure 1: the Core i7-5775C processor

We compared the performance of the Core i7-5775C with one of its predecessors, the Core i7-4770K. We also included the FX-9590 in the roundup, because it is the most high-end processor from AMD, despite the fact it is not a direct competitor to the Core i7-5775C, because it is in a different price range.

Figure 2: the FX-9590 (left), the Core i7-5775C (center), and the Core i7-4770K (right)

Let’s compare the main specs of the tested CPUs on the next page.