Towards the middle of the year, Intel is going to be launching their socketed Broadwell processors. These will be compatible with motherboards running the H97 and Z97 chipsets, with a slightly modified LGA 1150 socket that changes how power delivery happens inside the CPU. The socket change was necessary to support a new integrated GPU belonging to the Iris Pro family, but for over eight months Intel has been silent about how, or even if, the Broadwell launch was going to go ahead, with delays already moving the launch window for Skylake to late in Q3 2015. Still, the chips are coming and we’re going to be getting two of them in the consumer market – the Intel Core i7-5775C and the Core i5-5675C.
The rest of the Broadwell chips coming soon will be on the BGA 1364 socket, where they are soldered in to the motherboard and usually only available in OEM machines. These will be like the Gigabyte BRIX family, or the ASUS GR-line of small-form-factor PCs.
Broadwell, for those only coming out from under their rocks now, is a slightly revamped version of the Haswell architecture that is fabricated on the 14 nanometer production process and given a shot in the arm with some heavily upgraded graphics capabilities. That’s the real selling point of these chips, because Iris Pro 6200 also comes with the 128MB L4 cache of on-board, high-speed eDRAM. Having such a large slice of it practically negates the expense of adding in L3 cache to a chip, which is why these chips have less of it from the start.
Clock speeds are pretty low compared to Haswell on Intel’s 20nm process, with the top-end chip only reaching 3.8GHz with Turbo, which usually only boosts two cores to that frequency. Clock speeds are even lower at the base. The Core i5-4690K, the predecessor to the Core i5-5675C, has a range of 3.5 to 3.9GHz, while the Core i7-4790K has a 4.0 to 4.4GHz spread for Turbo. Hmmm.
The memory controller is different as well, almost certainly tuned for mobile applications from the start. There aren’t a lot of DDR3-L modules out there, so this might complicate things a bit if you go have to go sourcing RAM modules that operate at 1.35v. This Samsung RAM is pretty cheap, so bookmark it if you’re thinking of upgrading your rig for Broadwell.
Almost certainly, though, the lower clock speeds are an indicator that this hardware is probably going to run hot in several spots, and it will likely throttle itself much more aggressively to fall under the 65W TDP. Even though these chips are unlocked, that eDRAM is going to be producing a lot of localised heat that needs to be extracted from the integrated heatsink and out of the chassis. I think we’re going to see that some exotic cooling solutions will be needed if you expect to push up the clock speeds and the voltages.
I also think that if you’re going to overclock the GPU as well, your motherboard choices will be limited, as not every board compatible with these chips will have the necessary quality power supply to keep things running smoothly at higher frequencies and power draws. Its all really down to that eDRAM and its something that desktop PC owners have never had to deal with before. This will be an interesting launch to keep track of.
Source: VR-Zone China