Intel Core i7-6950X 10-core Broadwell-E Review
It has been nearly two years since the release of the Haswell-E platform, which began with the launch of the Core i7-5960X processor. Back then, the introduction of an 8-core consumer processor was the primary selling point; along with the new X99 chipset and DDR4 memory support. At the time, I heralded the processor as “easily the fastest consumer processor we have ever had in our hands” and “nearly impossible to beat.” So what has changed over the course of 24 months?
Today Intel is launching Broadwell-E, the follow up to Haswell-E, and things look very much the same as they did before. There are definitely a couple of changes worth noting and discussing, including the move to a 10-core processor option as well as Turbo Boost Max Technology 3.0, which is significantly more interesting than its marketing name implies. Intel is sticking with the X99 platform (good for users that might want to upgrade), though the cost of these new processors is more than slightly disappointing based on trends elsewhere in the market.
This review of the new Core i7-6950X 10-core Broadwell-E processor is going to be quick, and to the point: what changes, what is the performance, how does it overclock, and what will it cost you?
The Broadwell-E Architecture
As the name implies, the four processors that Intel is announcing today are part of the Broadwell-E platform, and utilize the same microarchitecture found in the Broadwell family. Desktop users never really got Broadwell parts; even though we included performance results from the Core i7-5775C here on PC Perspective, the part was never widely available, and was released much too close to Skylake to take seriously. Broadwell-E will very likely be more widespread in the DIY market than Broadwell was.
Inherently, there is an architectural disadvantage when going with Broadwell-E, as Skylake is on the market and widely available. Skylake offers improved power efficiency, upgrades and improvements to the integrated graphics, and some IPC enhancements. BDW-E however is a 140 watt CPU family that will surely be used with discrete graphics cards – Skylake’s advantages are less important in this particular market segment.
What is new to the enthusiast platform with BDW-E is a 14nm process technology, as earlier Haswell-E CPUs were built on the 22nm node. In theory this gives us more headroom for performance inside the same 140 watt power envelope. However, it would appear that rather than getting us extra clock speed, the process shift is what is allowing us to increase core count while maintaining competent clock rates.
So what does Broadwell-E offer for consumers? The new Intel Core i7-6900/6800 processor family will be the first to include a 10-core / 20-thread option under the Core brand, though Xeon parts have been available with equal or higher core counts for a while. They will also include as much as 25MB of cache. The addition of Turbo Boost Max Technology 3.0 is actually the most technically interesting addition to the processor family, promising to tell you which particular core is the “best”, and allowing it to work on single threaded workloads specifically.
The platform remains the same; X99 motherboards with the LGA2011-v3 socket should all be able to run the Core i7-6950X and other BDW-E CPUs with a firmware update. Of course, companies like ASUS and MSI are using this processor launch as a convenient time to update their existing X99 motherboard families with new features, and ASUS sent us the X99-Deluxe II to use in our testing. For users that are running Haswell-E today, this does offer an upgrade path for you to Broadwell-E. Whether or not that is a worthwhile move based on our performance results will be another discussion, but it is good that Intel is extending the lifespan of the platform at all.
Because Intel is sticking with the X99 chipset for Broadwell-E, we do not have any specific changes to talk about on the platform. Intel does mention in its presentation that Thunderbolt 3 is here, and a good match for Broadwell-E, but it will depend on the motherboard vendors to integrate support for it. Based on the new X99 boards I have seen timed with Broadwell-E, most of them do add Thunderbolt 3, USB 3.1, and U.2 storage support among other things, so I do expect the X99 boards coming out in 2016 to be better appointed than their 2014 counterparts.
Intel claims that performance increases will exist for both single and multi-threaded workloads. The multi-threaded performance improvements are easy enough to associate with the 10-core processor option, giving us 25% more cores than the Core i7-5960X. Single threaded improvements come courtesy of clock speeds and Turbo Boost Max 3.0 which we will discuss in a bit.
All four processors launching today are fully unlocked and allow for per-core overclocking, AVX specific offset ratios, and VccU voltage controls. More than likely these changes aren’t going to shift how normal overclockers get the job done, but it does give users that have a lot of experience with the art some additional room to stretch the silicon.
Let’s dive through the specs of the parts hitting shelves this summer.
The flagship processor for Broadwell-E is the Core i7-6950X, and it sports some impressive specifications! A base clock speed of 3.0 GHz along with a Boost clock speed of up to 3.5 GHz is paired with 10 cores to offer unseen multi-threading performance for a consumer branded processor. Obviously HyperThreading is in play so the CPU will actually address 20 threads in your system – and just looking at Windows Task Manager in that configuration is awesome. That CPU will have 25MB of cache, 40 lanes of PCI Express 3.0, quad-channel DDR4 memory support, and a price tag of $1723.
Wait, what?? $1700?!?
Intel has taken a different route with the Broadwell-E release than with the previous one. Every time Intel has increased core count on their Extreme Edition processors in the past, the new higher-core part was the flagship priced at $1000 or so. When Haswell-E brought us 8-core parts, it had a tray price of $1049. For whatever reason Intel is going back on that trend, keeping the 8-core processor option at $1089, but adding 58% to your price for 25% more cores. It changes the whole dynamic of the platform, honestly.
Looking past the Core i7-6950X to the other parts, Intel has an 8-core and two 6-core processors. The 8-core Core i7-6900K runs 200 MHz faster than the 6950X, drops a bit of cache (to 20MB) but maintains the same capabilities otherwise. Only the Core i7-6800 sees a drop in PCIe lanes – down to the same 28 lanes that the Core i7-5820K offered but with a price tag of just $434.