Cheese and crackers. Coffee and cream. Intel and AMD wouldn’t normally fit onto lists of two great tastes that taste great together, but the eighth-generation Intel G-series processors and their blend of blue-team CPU cores and red-team graphics might force a rethink as they launch this evening.
The way Intel sees it, the G-series CPU and GPU combo bridges an implementation divide that’s long existed between its 15 W U-series CPUs for thin-and-light notebooks and its 45 W H-series CPUs for high-performance notebooks. The obvious benefit of U-series CPUs in 15 W TDPs is that buyers can get the highest possible Intel CPU performance in ultra-portable machines, while H-series CPUs in 35 W and 45 W thermal envelopes provide the necessary muscle to chew through demanding computing tasks and feed high-end discrete graphics processors. Notebook buyers who want a machine that can do it all have generally had to accept higher noise, lower battery life, thicker chassis, and lots of heat production thanks to the power demands of high-performance discrete components.
The complete eighth-gen Core G-series package. Source: Intel
Intel’s vision for its G-series CPUs, then, is to give OEMs a way to build a thin-and-light notebook that’s closer in performance to bulkier systems with discrete graphics cards that typify the homes of current H-series CPUs. To do that, Intel G-series CPU packages join a high-performance, eighth-generation H-series CPU die with a semi-custom AMD Radeon graphics processor built for Intel called Radeon RX Vega M. Vega M is remarkable not only because it’s integrated on-package with an Intel CPU, but also because it’s the first midrange graphics implementation of the Vega architecture that we’ve seen so far.
|GTX 1060 3 GB||1506||1708||48||72||1152||192||192 GB/s||3 GB||185 W|
|GTX 1060 6GB||1506||1708||48||80||1280||192||192 GB/s||6 GB||120 W|
|RX Vega M GH||1063||1190||64||96||1536||1024||205 GB/s||4 GB||—|
|GTX 1050||1354||1455||32||40||640||128||112 GB/s||2 GB||75 W|
|GTX 1050 Ti||1290||1392||32||48||768||128||112 GB/s||4 GB||75 W|
|RX Vega M GL||931||1011||32||80||1280||1024||179 GB/s||4 GB||—|
|RX 560 (1024 SP)||1175||1275||16||64||1024||128||112 GB/s||2 GB/4 GB||80 W|
|RX 570||1168||1244||32||128||2048||256||224 GB/s||4 GB||150 W|
Intel will ship Vega M graphics processors in two forms. The entry-level member of this family, Radeon Vega M GL, will accompany the trio of Core i5 G processors launching today. This chip features 20 Radeon Vega compute units, for a total of 1280 stream processors. Alongside that shader engine, the Vega M GL offers 80 texturing units and four geometry engines, and its ROPs can output 32 pixels per clock. The M GL will run at a base clock of 931 MHz and a boost clock of 1011 MHz.
The higher-performance Radeon Vega M GH will accompany the duo of Core i7 CPUs in the G series. This potent GPU offers 1536 stream processors across 24 Vega compute units, 96 texture units, four geometry engines, and it can output 64 ROP pixels per clock. Intel specifies this part for a base clock of 1063 MHz and a boost clock of 1190 MHz.
Both Radeon Vega M chips are joined with a single stack of HBM2 RAM with a 1024-bit-wide memory bus. Until recently, joining HBM2 with another chip has involved placing those components together on a silicon interposer—a design requirement that’s more expensive, more complex, and more restrictive than joining components together on the same PCB.
The Intel G-series CPU package takes a different approach for joining HBM2 with the GPU. It’s the first Intel consumer product to use the company’s Embedded Multi-Die Interconnect Bridge (EMIB) technology, a data-only connection that allows two chips to be placed extremely close together on package with high signal integrity and high bandwidth.
An EMIB is, in short, a small piece of silicon that’s embedded into the underlying package. This sliver of silicon has a number of routing layers inside that can be used to connect two discrete components over very short distances and with very high interconnect density. In this case, the HBM2 RAM uses a single EMIB to communicate with the Vega M GPU. On top of its less-complex implementation, using an EMIB reduces the overall height of the processor package—a critical point in the never-ending race toward thinner and lighter notebooks. Intel says building this same chip on an interposer would result in a significantly thicker package.
Intel clocks the 4 GB of HBM2 RAM paired with the Vega M GL chip at an effective 1.4 Gbps for peak aggregate bandwidth of 179 GB/s. The Vega M GH chip gets a higher-speed 4-GB slice of HBM2 running at 1.6 Gbps for aggregate bandwidth of 205 GB/s. Unlike the custom memory controller of AMD’s Raven Ridge APUs, Vega M retains the Vega architecture’s high-bandwidth cache controller for communication with the HBM2 stack.
The RX Vega M GPU, in turn, is connected to the CPU by eight PCIe 3.0 lanes from that chip. Platform engineers can then choose to allocate the remaining eight PCIe lanes from the CPU to platform devices like M.2 slots or Thunderbolt controllers.
Smarter power leads to higher efficiency
With the basic building blocks we just outlined, Intel will offer five versions of these eighth-generation G-series CPUs in BGA packages only for now. Three of those chips will have 65 W power envelopes in Core i5 and Core i7 flavors, and two more will slot into 100 W envelopes in Core i7 form only. Just bringing the Intel and AMD pieces of the puzzle together on-package isn’t enough to ensure the best performance from this idea, though. To allow each component on the package to perform at its best within those power envelopes, Intel says it did a lot of work on the software layer of the G-series platform to dynamically allocate just the right amount of power to each component on the package under a given workload.
That dynamic power management is critical to getting the most out of G-series CPUs’ thermal envelopes. Whereas manufacturers integrating a CPU and a discrete GPU in a notebook might have had to build a laptop around a combined system design point (SDP) in the past that was unrepresentative of the power demands of those components in their typical use cases, Intel says its “Dynamic Tuning” software control lets it allocate power in real-time based on actual workloads. Intel claims this dynamic power-sharing arrangement can result in a lower real-world TDP for the whole package that lets designers extract similar levels—if not higher levels—of performance than those same components operating from a static scenario design power assumption.
For example, the company shared figures showing the kinds of efficiency gains that can arise from using Dynamic Tuning versus a system without the technology enabled. Dynamic Tuning results in a higher “frames per watt” figure than the same chip running without the power-management feature. The benefits of Dynamic Tuning end up allowing manufacturers to design thinner notebooks with the same performance of a thicker system that might have been designed with a higher SDP.
Not only is the G-series package smarter about power usage than discrete components without such dynamic power-monitoring capabilities, it’s also just plain smaller than a CPU and a discrete GPU with GDDR RAM that have to be mounted on the same motherboard. Intel touts a savings of 1900 mm² (or three square inches) of board area with a G-series package compared to today’s discrete layouts. Intel says system designers can use that precious space to include larger batteries or larger fans, or simply to build a smaller chassis overall.
|RX Vega M GH||UHD 630||No||100 W||Yes|
|i7-8706G||RX Vega M GL||Yes||65 W|
Despite the eighth-generation naming scheme, the CPU side of the G-series package is essentially Kaby Lake-H carried over. The same Skylake core we’ve known since August 2015 is playing another set here, and the five G-series parts launching today share more in common than not from their CPUs. Like Kaby Lake Refresh chips, all of these chips offer four cores and eight threads of processing resources, and they’ll all have Intel’s HD Graphics 630 IGP on board if users want to take advantage of capabilities like Quick Sync or the extra display outs that manufacturers can tap from them. Within thermal envelopes, their differences come down to clocks, L3 cache, and enterprise management capabilities.
The two Core i7 parts with 100 W TDPs will likely be of most interest to enthusiasts. Both come with 8 MB of cache, RX Vega M GH graphics with 4 GB of HBM2, and 3.1 GHz base speeds. The Core i7-8809G is the top-end member of the entire G-series family. It’ll be the only such part with fully-unlocked CPU, GPU, and HBM2 RAM clocks, and it has the highest stock boost clock speed of the bunch, at 4.2 GHz. The Core i7-8709G loses the unlocked multipliers and drops 100 MHz of boost-clock speed. It’s otherwise identical to the i7-8809G. Neither part offers vPro support.
The 65 W family of G-series processors offers three chips to choose from. The Core i7-8706G has vPro support, while the i7-8705G does not. Both chips have 8 MB of L3 cache and share 3.1 GHz base and 4.1 GHz boost clocks. The Core i5-8305G gets relegated to the bottom of the 65 W stack with a 3.8 GHz boost clock and a 2.8 GHz base clock. All three chips share the same Radeon RX Vega M GL graphics processor and 4 GB HBM2 RAM capacity.
A marriage of convenience
Some might wonder why Intel tapped a competitor’s GPU technology to make G-series processors a reality when it already has a fine internal GPU team of its own. The way Intel sees it, the on-package integration it’s performing is no different, philosophically, from what notebook makers themselves are doing in the enthusiast graphics space when they hook up an Nvidia or AMD GPU to an Intel H-series CPU in an enthusiast notebook. The move to bring Radeon graphics on package, then, seems at once a stopgap and a warning shot.
Intel’s most powerful integrated graphics processor so far, the Iris Pro 580, very broadly tops out at about the point where entry-level discrete graphics chips from Nvidia and AMD start to take the stage. Intel can likely scale its Gen architecture (or another new microarchitecture) into a discrete chip to fulfill its ambitions to compete in discrete graphics again, but if it does so, that work could take a fair amount of time—time that Nvidia will continue capitalizing on with its dominant lineup of mobile enthusiast graphics processors. By bringing a Vega GPU on package today, Intel offers notebook makers a ready alternative that literally leaves no room for an Nvidia GPU in a system.
|GTX 1060 3 GB||82||123/123||3.4||3.9|
|GTX 1060 6 GB||82||137/137||3.4||4.4|
|RX Vega M GH||76||114/57||4.8||3.7|
|GTX 1050 Ti||45||67/67||2.8||2.1|
|RX Vega M GL||32||81/40||4.0||2.6|
If Intel is developing graphics processors of its own for use in integrated packages like these G-series parts, the expected performance of the Radeon RX Vega M GL and Vega M GH might point to where Intel’s own chips might begin drawing battle lines against the green team.
Intel claims that a 65 W implementation of a Core i7-8705G and its Vega M GL generally ekes out wins against a Core i7-8550U in 15 W trim alongside a GeForce GTX 1050 4 GB in the three titles it chose to share data for at 1920×1080 and high setttings. Running Hitman and Deus Ex: Mankind Divided in their DX12 modes might disadvantage the GTX 1050 more than DX11 might, and we’d still want to see 99th-percentile frame times for these titles to really get a sense of whether either chip is truly delivering playable performance. Still, head-to-head results like these seem promising for the RX Vega M GL.
Intel also matched up a 100 W implementation of the i7-8709G with a notebook configuration typical of many gaming laptops nowadays: a Core i7-7700HQ paired with a GeForce GTX 1060 Max-Q graphics chip. (Max-Q essentially means a lower-TDP variant of a given Nvidia mobile graphics chip.) With the same caveats I raised for the RX Vega M GL-vs.-GTX-1050 comparison, the i7-8709G seems poised to deliver 1920×1080 gaming performance similar to that of the Max-Q notebook in a similar system design point (the Max-Q GTX 1060 slots into 60 W or 70 W, while the Core i7-7700HQ in Intel’s test rig was configured at 45 W).
We don’t know how expensive notebooks with Intel G-series processors will be yet, but these early performance numbers would seem to promise that sparks will fly once we do get our hands on those systems and start testing. However those real-world numbers shake out, make no mistake: Intel is gunning for a slice of Nvidia’s lucrative mobile-graphics pie, even if it has to enlist another ostensible foe to get there.
The most muscular NUC yet
We can’t talk about the full details of Intel’s notebook design wins with eighth-gen G-series processors just yet, but we can say that systems from Dell and HP are coming down the line. That lack of detail is fine for the moment, because Intel is revealing an exciting product of its own this evening: the next iteration of its high-performance NUC, called the NUC 8 Enthusiast family.
Code-named Hades Canyon, the beefiest next-gen NUC will serve as a showcase for the 100 W version of the Core i7-8709G. Despite its tiny 1.2 L volume, this NUC8i7HVK version of the NUC 8 Enthusiast will still sport fully-unlocked multipliers on its CPU cores, GPU, and HBM2 RAM, though it’ll remain to be seen just how far tweakers will be able to push the chip in practice.
With all that processing power inside, Intel thinks there’s little that Hades Canyon can’t do. The company says the NUC 8 Enthusiast is ready for premium VR, high-resolution gaming, and demanding productivity application across as many as six monitors. The NUC 8 will sport copious peripheral I/O, including two Thunderbolt 3 ports, dual M.2 slots, a front HDMI 2.0b out, a rear HDMI 2.0b out, two Mini DisplayPort 1.3 connections, two Gigabit Ethernet jacks, seven USB ports, an SD card reader, and TOSLINK digital audio output.
For folks still looking for plenty of processing power from a small-form-factor system at a more affordable price point, Intel will also offer a NUCi7HNK version of the NUC 8 with a Core i7-8705G CPU inside. The cherry on top of both of these systems is, of course, an RGB LED-illuminated skull logo emblazoned on a removeable lid that enterprising builders can customize to their liking with a 3D-printed replacement.
Intel’s NUC 8 Enthusiast system will begin shipping to enthusiasts in late March. The company says systems from its partners will arrive sometime in the spring of this year. We’re eagerly awaiting an opportunity to put these systems through their paces.