Intel Broadwell i7 5775C Review & Overclocking
Intel Broadwell i7 5775C
ASUS Z97A USB 3.1
Corsair Vengeance Pro 2400
Corsair Neutron GTX
Custom Corsair 540 Air
Windows 7 x64
When it came to getting our Z97 test rig up and running we did have a few issues which we thought we would bring up to possibly help with the confusion we ran into. We installed our CPU and booted the system fine, downloaded the latest BIOS and got that installed even easier but we couldn't get the system to run XMP and much more disappointingly do any form of overclocking. It turns out a normal BIOS flash wont actually update the microcode at a low enough level to get everything working as it should. You can use the Asus USB BIOS Flashback feature via a USB pen but Asus do have a handy tool that you can find where you would download the drivers for your specific motherboard. Its a windows based tool which we would normally avoid like the plague but this is incredibly simple to use and worked without and fuss for us and got the system firing on all cylinders with the XMP and overclocking fixed in just a couple of minutes.
Such is the newness of the i7-5775C that we had a choice of waiting an age for a mature BIOS to maximise the overclocking, or test it at stock and concentrate on the Iris 6200. Given that the iGPU side of the Broadwell CPUs is definitely the big selling point, we focussed mainly upon that. That isn't to say that the i7-5775C is lacking in horsepower though. Despite the enormous amount of silicon dedicated to graphical prowess, the i7 still has all the bells and whistles one would expect from a range-topping Intel CPU. 3.7GHz is hardly slow, particularly when the i7-5775C has hyperthreading.
We only managed to get a 4.2GHz overclock out of the Broadwell chip we were sent which by previous generations of i7's seems a touch low. We do need to remember this is the first CPU we have had our hands on from the 14nm manufacturing process so things still may be a little raw. Voltage didn't help when trying to push further than this so we stuck with a safe voltage. Normally we would run some overclocked CPU tests but as we have tweaked our usual testing procedure to focus on the iGPU we didn't feel the need to confuse matters by adding another set of tests to the graphs.
The Iris 6200 is outstandingly efficient, helped in no small part by the 14nm process. This has other benefits too as even with the CPU and Iris in full effect the i7-5775C only reached 60°C. The 4790K pull less power in the GPU tests mainly because of the lack of any real power, the big figure here is the massive drop in power usage on the CPU only tests, if this is what 14nm will deliver across the board things could be getting very interesting.