The missing link between Haswell and Haswell-E has been found...
The top end of Intel’s Haswell-E platform is where all the finest new technology from this generation of performance computing lies. When you’ve got the fastest PCIe-based storage connections, a brand new generation of system memory and a full eight-core consumer processor pulling it all together, that’s the pinnacle of today’s PC tech right there.
Quite rightly then, the Core i7-5960X, with its 16 threads of processing power, got all the initial headlines. But for us, this bargain-priced six-core Core i7-5820K is the most interesting CPU of this latest chip generation.
We’re penny-pinchers here y’see – our meagre salary allows for but one bowl of subsidised Soylent Gruel to sustain ourselves each day – so the prospect of
the cheapest Intel six-core processor ever is a tantalising one. Last generation’s Core i7-4930K, of second-tier Ivy Bridge-E fame, was the previous winner of that dubious accolade, though was still a £500 processor at the time of launch.
The Core i7-5820K, however, is £200 cheaper than the older silicon – and considerably quicker too. In fact, it’s also quicker than Ivy Bridge-E’s top CPU, the Core i7-4960X, and that is still an almost £800 processor. The 5820K is a CPU of full Haswell-E stock, sharing the same silicon DNA as the top eight-core 5960X. So, it’s still the same 22nm 4th Gen Core architecture and fits in the same advanced X99 platform as its bigger brothers.
All you’re missing out on compared to either the i7-5960X is those two cores, 5MB of cache and 12 PCI e lanes. Compared with the £450 i7-5930K (the similarly six-core middle child of the three Haswell-E siblings) you’re just getting a slightly slower chip with fewer of those PCI e lanes.
What we’re getting at here is this processor is still seriously powerful. We’re talking about proper advanced Intel silicon, and it’s retailing for only a little more than the quad-core Devil’s Canyon processors from the latest standard Haswell refresh.
Chips aren’t free
But affordable six-core CPUs are nothing new, right? After all, you can get an AMD six-core processor for just £75 right now.
However, what AMD considers six-core isn’t the same as the way Intel counts cores; if it was, we’d be talking about the 5820K being a 12-core chip. The modular CPU design brought in with Bulldozer was essentially AMD’s take on Intel’s HyperThreading, but with just a little more actual silicon added to the multithreaded mix. But AMD looks like it has seen the error of its ways and is likely to be switching back to a more traditional CPU design when its Zen architecture finally sees the light of day a few years from now.
The most intriguing part about this latest range of Extreme edition chips is that we’re finally seeing a more linear path from Intel’s lower order CPUs right through to its top, £800 behemoths. Before there was a big price jump up from the likes of an Ivy Bridge quad-core up to an Ivy Bridge E six-core, with an extraneous, expensive quad twiddling its thumbs awkwardly in between the two. With the i7-5820K being just £30-40 more expensive than the i7-4790K anyone who was looking at the top Devil’s Canyon CPU for their machine now has an interesting choice to make regarding their PC’s platform.
We’re not going to pretend that’s the only price difference between a decent Haswell setup and the Extreme edition version, but without having to sacrifice any real performance you can build a six-core X99 setup for just £100 more expensive than a quad-core Devil’s Canyon Z97 machine. Prices of DDR4 are high, but when you’re looking at dropping 16GB of RAM into your rig – which is something you’d probably want to do if you’re going to utilise the productivity power of the 12 processing threads – there’s not a great difference between 16GB of 1,600MHz DDR3 and 16GB of 2,133MHz DDR4. If you go for the basic, but powerful Crucial kit we checked out a couple of issues back, the difference can be less than £20.
So if the sorts of things you do with your PC are going to use the processing power that a bona fide six-core CPU can offer, like AV manipulation/creation or heavy rendering tasks, then the i7-5820K is an incredibly good value piece of technology. The processing and memory performance of the X99 platform is so far in advance of a Z97/4790K combo the £100 premium looks like a winner.
But if you’re more likely to be cutting down Uruks in Mordor than creating masterpieces in Premier Pro, then the extra expense is likely to be wasted. Current game engines still can’t make use of the extra core count of something like the 5820K, and so you don’t see any real performance increase for your extra spend. And don’t get us started on what little difference system memory makes in-game.
Money for nothing
But what about multi-GPU setups? With the extra PCI e lanes of Haswell-E, surely an SLI / CrossFireX rig will perform better on an X99 with an Extreme edition CPU, right? You can see where we’re going here. Because the 5820K still only has 28 PCI e 3.0 lanes it’s not able to run a pair of cards at x16 speeds, only the 5930K and 5960X can do that with their 40 lane capacities. But given PCI e 3.0 offers way more bandwidth than our cards use there’s actually little performance difference between running with both cards at x8 speeds as at x16.
If you’re chasing the diminishing returns of a three-way GPU setup, however, the 5820K will ensure you get x8 performance on all three rather than one defaulting to a struggling x4 speed. That is an incredibly small niche of computing though, and the only place where a 5820K can really get the jump on Devil’s Canyon in terms of gaming.
The future of multi-core performance looks set to get a helping hand with DirectX 12 next year though, and that might be enough for those looking to build a future-proof machine right now. This powerful six-core CPU isn’t going to be superseded anytime soon – Broadwell-E has been pushed back to 2016 – and with this platform in place you’ll have serious high-end processing power for years to come. Dave James
Vital statistics
Price £282
Manufacturer Intel
Web www.intel.com
Socket Intel LGA 2011-v3
Core technology Intel 4th Gen Core
Clockspeed 3.3GHz
Turbo 3.6GHz
Cores 6
Threads 12
Lithography 22nm
Cache 15MB
TDP 140W