Intel Launches 7th Generation Kaby Lake: 15W/28W with Iris, 35-91W Desktop and Mobile Xeon
by Ian Cutress on January 3, 2017 12:01 PM ESTA Brief Rundown of Results for Kaby Lake on Desktop
At the time of writing this, we’ve managed to test all three overclockable SKUs and started on the 65W parts as well. Each of the K parts will have their own dedicated reviews which we thoroughly recommend to understand more about the specific products, but here’s a page to give a brief overview of performance.
IPC: No Change in CPU Performance (link)
As was to be expected, especially judging on how Intel described the upgrade between Skylake and Kaby Lake, there is no IPC gain between the two for direct performance. In our testing, a 3.0 GHz Core i7-7700K Kaby Lake part performed identical to a 3.0 GHz Core i7-6700K Skylake processor (HT disabled). The only difference is really in the memory support, given that Skylake supports DDR4-2133 and Kaby Lake supports DDR4-2400, however this has a minor effect on almost all benchmarks.
One thing I will note is that on the motherboards we tested with, some of them implemented the full supported FCLK frequency (1000 MHz) rather than the BIOS base (800 MHz) when it dedicated a K-CPU in. The FCLK issue we documented on Skylake was down to a rush to get the higher speed certified before the launch, but as a result we saw 800 MHz being the main frequency used (and BIOS updates required to even offer 1000 MHz as an ‘overclockable’ option). So while Kaby Lake seems to go at 1000 MHz out of the box, depending on which motherboard you use, from our testing we didn’t see much change in GPU performance when both CPUs are at 3 GHz.
Power
One of Kaby Lake’s big things has been ‘same frequency for less power’, or ‘more frequency for the same power’, compared to Skylake. After all, if you want more performance out of the box but don’t have an IPC gain, then a higher frequency is required. On the box of the i7-7700K it will say that it supports a 4.5 GHz turbo with a 91W TDP, and in our power testing we practically match that number (leaving aside the fact that TDP != power consumption).
For all the Kaby Lake SKUs we tested, even when manual overclocking, the power consumption of the part was very close to the rated TDP at the box frequency. Normally when we overclock we find that the CPU vendor has vastly overestimated the voltage required to be ‘AnandTech Stable’, but in the case of Kaby Lake we saw numbers that were very close.
Overclocking
Overclocking perceptions will change with Kaby Lake, due to the new AVX Offset feature to be found in the BIOS of each Z270 motherboard. AVX instructions are known to cripple a good overclock, reducing the stability and making it harder to push the non-AVX code if that is the limitation. With Kaby Lake, a user can apply an AVX offset (e.g. -10x) which will reduce the multiplier when an AVX instruction occurs. This means that if an overclock of 4.8 GHz is reached and an AVX Offset of 8x is in play, then the AVX instruction will run at 4.0 GHz, generating less heat and keeping the system stable.
We will have a dedicated overclocking piece going over all our OC results, but the short of it is that all three of our K-SKUs (retail parts) happily reached 4.8 GHz AVX at a reasonable voltage. The i7-7700K was able to hit 4.9 GHz with an AVX offset of -10, and our i5-7600K hit 5.0 GHz even with AVX turned on.
Ultimately overclocking a 4.2/4.5 GHz CPU in the i7-7700K to 4.8 GHz isn’t much of a step. This will be one of the big results from the launch of Kaby Lake for enthusiasts: overclocking the high-end SKU doesn’t actually do that much. Another 600 MHz on top of 4.2/4.5 GHz is +13-14%, which is not that much. However, given the voltage profile of the chips we’ve seen, just sitting at 4.5 GHz all day is nice for temperatures and voltage, and still gives a CPU that outperforms the i7-4790K or i7-6600K.
Performance
Read our Core i7-7700K review here.
Read our Core i5-7600K review here.
Read our Core i3-7350K review here.
At the end of the day, the Core i7-7700K takes the performance crown for practically every benchmark (there are a few in which the i7-5775C still wins, due to 128MB of eDRAM), and has a tray price of $305. This means it will probably reach shelves around $330-$350, and we haven’t heard about a new stock cooler so it will probably come without one.
The Core i5-7600K still keeps the mantra of how a Core i5 performs almost the same as the Core i7 except in lightly threaded scenarios (ray tracing), but for day to day work it certainly keeps neck and neck. The downside here is that the Core i5-7600K, due to the lack of an IPC increase, is essentially the Core i5-6600K save for a few MHz. You could consider that ours overclocked well, and the temperatures for the overclock were immensely better than the i7-7700K, but for running at stock there’s nothing out of the ordinary here.
The elephant in the room however is the Core i3-7350K. At a tray price of $159, it is only $11 away from the Core i5-7400 which runs at $170 but has two more full cores, albeit at a lower frequency (3.0/3.5 GHz vs 4.2 GHz all the time). If you want to see our analysis, and what we think, I’ll leave it to the review to tell you. We also look at the question as to whether something like the Core i3-7350K will ever reach the same performance as the perennial favorite, the i7-2600K.
Is Intel Breaking New Ground?
For the most part, Kaby Lake doesn’t do much new. Optane Memory support is a plus, but the rest of the product stack is all about moving the power and efficiency curve. What used to get you 3.0 GHz last year now gets you 3.3 GHz, which means saving time doing work or saving money burning less power. There’s also Speed Shift v2, which is a really nice feature, but is limited to Windows 10 users. Arguably looking at the controller side (ALC1220, E2500, Aquantia) is vaguely more interesting. But this is what we kind of expected from an ‘Optimization’ step in the ‘Process, Architecture, Optimization’ way of doing things: we weren’t expecting to be amazed with the product, but nodding and approving of better efficiency. The fact that there’s a new performance champion gives us something to cheer about after the Skylake/Devil’s Canyon discussion is a plus for enthusiasts with a short upgrade cycle.
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Lolimaster - Tuesday, January 3, 2017 - link
Considering the minimum cores you get per module is 4, I see AMD selling months later a 3c/6t cpu for $99.They will make a tweak for the raven ridge APU since the core count for those is 4c max.
jjj - Friday, January 6, 2017 - link
Every segment they don't cover (and they don't have Zen APUs yet) is business left on the table - the budget segment is big enough and in regions they care about.Maybe they should go to 49$ with quads and disable HT, some cache but it is likely that if they don't do that, most would make an effort to get the 99$ quad. Just hope they don't get too greedy and start way higher, Intel can make quads without a GPU too, won't take too long and AMD needs to exploit this window of opportunity and gain,not just revenue, but hearts and minds.
name99 - Tuesday, January 3, 2017 - link
"We still have not received an official word if Intel is working closely with Apple to bring the feature to macOS, or even if it will be promoted if it ever makes the transition"Could some more-or-less unexpected interaction between Speed Shift 2 and the rest of MacOS be the reason for the apparently random dramatic swings in the battery lifetime of the new MacBook Pros? We hardly know enough to point fingers at either Apple or Intel, but I could certainly imagine that each side has a certain mental model of what the other side is/"should" be doing, and the mismatch between those models means that the CPU is randomly being told to run at maximum speed when the OS actually wants it to dramatically slow down.
I agree that this sounds kinda dumb of the surface, but I could imagine that there are enough layers between UI/framework code, the power driver, the core OS, and EFI, that something gets confused along the way including, perhaps, exposing a bug (again either on the Apple side or the Intel side) that just didn't get triggered (or at least not very often) on either previous x86 CPUs or on Linux/Windows.
rodmunch69 - Tuesday, January 3, 2017 - link
My 5 year old 3930k can still basically keep up with Intel's latest and greatest with stock voltage OC. Hum... I used to buy new stuff every year, or every two years at most, because there was normally a good gain to be had. It's legit been 5 years now and my PC with a little work, in multi core tests, is just as fast as anything out there. That's pitiful on Intel's behalf. They've gotten fat and lazy and the consumer is paying for it. Trump needs to tell AMD to put the A back into their chips and actually put out some products at the high-end that actually pushes Intel to be great again.Laststop311 - Wednesday, January 4, 2017 - link
Is it really worth saving 60 dollars to get an unlocked i3 vs the unlocked i5? I really can't see any situation where 60 dollars is the difference between being able to afford a new pc or not. With DX12 it HIGHLY benefits from having 4 cores (really 6 cores is optimum with 8 only slightly improving). Being stuck with 2 cores in this day is severely crippling your lifespan of the pc. You will waste GPU power and be constrained by the 2 cores all in the name to save 60 dollars. Nah it's not worth it.Kaby lake in general is not worth it. Everyone with quad core sandy bridge and above is going to see very minimal gains from a quad core cpu. You really need to go to 6 cores to get any real performance increase and you also need to be playing in dx 12 mode. Your best bet is to wait for the 2019 tock of 10nm coffee lake. Intel will be moving to pci-e 4.0 which doubles the bandwidth so an 8x pci-e 4.0 is the same as a 16x pci-e 3.0. Since gpu's only lose a few percentage points of performance on 8x pci-e 3.0, 8x pci-e 4.0 will give them all the breathing room they need. This leaves you 16x lanes of the 24 lanes to use for m2 storage devices or capture cards without having to use the higher latency PCH pci-e lanes. Or with multi GPU you still have 8x cpu pci-e lanes and you only need 2x pci-e 4.0 lanes to give you 4GB/s (32gbps) so you can fit dual gpu's and 4 pci-e storage devices all connected to the cpu directly and both gpu's will get 16GB/s (128gbps) bandwidth. This gives you massive future proofing. With intel optane maturing you can go single gpu at 16x pci-e 4.0 lanes 32GB/s bandwidth (256gbps) stick an optane drive on 4x lanes giving you a massive 8GB/s (64gbps) and 2 m2 nvme ssd's on 2x lanes each 4GB/s (32gbps) each, with all devices connected directly to CPU for the lowest latency leaving all the PCH lanes free for external ports like TB3 USB 3.1 gen 2 etc.
By waiting till 2019 you get a real upgrade instead of a sidegrade. pci-e 4.0 will unlock the true potential of Intel optane as i expect by then the optane drives will be maxing out the 4x pci-e 3.0 lanes at 4GB/s and pci-e 4.0 will allow optane to really shine and most likely hit 7GB/s or more. With that kinda storage speed you can transfer an entire blu ray disc image in about 7 seconds.
Now by all means if you are still on the Q series quad cores than kaby lake is a compelling upgrade and isn't a total waste of money to upgrade. But even in that circumstance I would say try to stick it out another year so you can have a 6 core coffee lake as 6 cores is incredibly useful in dx12.
Lolimaster - Wednesday, January 4, 2017 - link
You mean upgrade to the 8c/16t Ryzen or wait 2018-2019 for the 7nm Zen+?gopher1369 - Wednesday, January 4, 2017 - link
The only thing that occurs to me is game emulators. Dolphin and PCSX2 require high clock speeds and high IPC, not more cores. It's quite niche, but if you're building an emulator box then the unlocked Anniversary Edition Haswell Pentium is currently the go-to processor, the new i3 should be even better.Laststop311 - Wednesday, January 4, 2017 - link
What applications use AVX instructions? I wonder how much it will hurt performance for some applications by decreasing AVX to 4.0ghz so you can hit 5.0ghz on everything else. The highest overclock i've seen talked about is 5.1ghz on the i7-7700k using the corsair 115ijohnp_ - Wednesday, January 4, 2017 - link
(3) Embedded DisplayPort* (eDP) 1.4 and PSR2 under evaluationI seriously didn't expect that! This means that they actually changed the display pipeline slightly :)
Now, hopefully laptop vendors will make use of PSR2 to further improve battery life.
On a side-note: Does anyone know how to overclock the 7820HK when there's no mobile chipset that supports overclocking? Will laptop vendors have to include the Z270 desktop chipset on their platform?
keeepcool - Friday, January 6, 2017 - link
You open intel XTU and press on the arrows till it BSOD's.Laptop chipsets are "different" in a lot of senses.