Intel Xe Graphics: Release Date, Specs, Everything We Know

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Intel Xe Graphics will join the dedicated graphics card fray this year, but can it possibly compete with AMD and Nvidia GPUs?

Last year, Intel Xe Graphics was announced, along with Intel's intention to re-enter the discrete GPU space, the first time we'll have a dedicated Intel GPU since the i740 back in 1998. The competition among the best graphics cards is fierce, and Intel's current integrated graphics solutions don't even rank on our GPU hierarchy (they'd be about 1/3 the performance of even a low-end card like an Nvidia GT 1030). Could Intel, purveyor of low performance integrated GPUs—"the most popular GPUs in the world"—possibly hope to compete? Yes, actually, it can.

This year promises a massive shakeup in the PC graphics card market. AMD is working on Big Navi / RDNA 2, Nvidia's RTX 3080 / Ampere GPUs are coming, and along with Intel's Xe Graphics there are rumblings of a fourth player potentially entering the PC GPU space. Huawei is reportedly entering the data center GPU market, so it's not a huge leap to imagine it making consumer models at some point. But for this article, we're focusing on Intel.

Intel's Xe Graphics aspirations hit center stage in 2018, with the hiring of Raja Koduri from AMD, followed by chip architect Jim Keller and graphics marketer Chris Hook, to name just a few. Raja was the driving force behind AMD's Radeon Technologies Group that was created in November 2015, along with the Vega and Navi architectures, and clearly the hope is that he can help lead Intel's GPU division into new frontiers. Not that Intel hasn't tried this before. Besides the i740, Larrabee and the Xeon Phi had similar goals back in 2009, though the GPU aspect never really panned out. So, third time's the charm, right?

Of course, there's a lot more to building a good GPU than just saying you want to make one, and Intel has a lot to prove. Here's everything we know about the upcoming Intel Xe Graphics, including release date, specifications, performance expectations, and pricing. 

Intel Xe Graphics Architecture

While Intel may be a newcomer to the dedicated graphics card market, it's by no means new to making GPUs. Current Intel Ice Lake CPUs use the Gen11 Graphics architecture, which as the name implies is the 11th generation of Intel GPUs. Incidentally, the first generation of Intel GPUs was in its last discrete graphics card, the i740 (along with Intel's 810/815 chipsets for socket 370 Pentium III and Celeron CPUs, circa 1998-2000). Xe Graphics is round 12 for Intel GPU architectures, in other words, with Gen5 through Gen11 being integrated into Intel CPUs of the past decade. Note that Gen10 Graphics never actually saw the light of day, as it was part of the aborted Cannon Lake CPU line.

While it's common for each generation of GPUs to build on the previous architecture, adding various improvements and enhancements, Intel is reportedly making major changes with Xe Graphics. Some of those changes focus on enabling the expansion of GPU cores, others address the need for dedicated VRAM, and there will also be changes focused on improving per-core performance and IPC.

Recent Intel GPUs have been divided up into a number of 'slices' and 'sub-slices,' with the sub-slices being somewhat analogous to AMD's CUs and Nvidia's SMs. Gen9 Graphics has a sub-slice size of 8 EUs, and each EU has two 128-bit floating point units (FPUs). For FP32 computations, each EU can do up to 8 instructions per clock, and FMA (fused multiply add) instructions count as two FP operations, giving a maximum throughput of 16 FP operations per clock. So: EUs * 8 * 2 * clock speed = GFLOPS. In that sense, an EU counts as eight GPU cores when compared with AMD and Nvidia GPUs, and 8 EUs is equal to an AMD CU or Nvidia SM.

Stepping out one level, the slices in previous Intel graphics have been classified as GT1, GT2, GT3, and GT4 (with Ice Lake / Gen11 adding a GT1.5 option). For Gen9, GT2 models have three sub-slices with eight EUs each, GT1 has two sub-slices with six EUs enabled in each, and GT3 has six sub-slices and eight EUs each. Gen11 changed to each slice having four sub-slices of eight EUs, so Ice Lake GT2 has 64 EUs and 512 GPU cores. For Xe Graphics, Intel will be going for significantly higher EU counts and larger GPU sizes.

Current indications are that the base 'slice' size for Xe Graphics will have up to 64 EUs enabled, with different configurations having different numbers of slices and sub-slices that can be partially disabled as needed. The fundamental building block for Xe Graphics ends up being basically the same as Gen11 Graphics, at least for the first iteration. The big changes will involve adding all the logic for dedicated VRAM, scaling to much higher core counts and multi-chip support, along with any other architectural changes that have yet to be revealed. Xe Graphics will have full DX12 and Vulkan support, but beyond that is unknown.

Intel has talked about three broad classifications of Xe Graphics: Xe LP for low power / low performance devices, Xe HP for high performance solutions, and Xe HPC for data center applications. Xe LP as far as we can tell is mostly for integrated graphics solutions, likely with a single slice—maybe two in a few cases. We know Xe LP is in the upcoming Tiger Lake CPUs, and it was used in the Xe Graphics DG1 developer card. It will be the next iteration of Intel's processor graphics, in other words.

At the other end of the spectrum, there have been images and details regarding Xe HPC and Intel's Exascale ambitions for supercomputers, which as you might imagine means incredibly powerful and expensive chips—we don't anticipate Xe HPC GPUs showing up in consumer cards any time soon. The most interesting chips from our perspective will fall under the Xe HP umbrella, and these should show up in a variety of consumer graphics cards.

One thing that's still unclear is whether the first Xe Graphics solutions will support hardware ray tracing or not. Intel has said it will support ray tracing, but it hasn't specifically stated that it will happen with the initial Xe Graphics architecture. It seems more likely that ray tracing will come in the second generation of Xe Graphics, the 7nm Ponte Vecchio and related chips. Or perhaps ray tracing support will be in a limited subset of the first gen parts—high-end Xe HP or HPC, but not Xe LP, for example. We don't know yet, but it would be quite surprising to have full ray tracing arrive before AMD's ray tracing solution.

These architectural updates are critical, as current Intel GPUs are at best underwhelming when it comes to gaming performance. Take UHD Graphics 630 as an example: 24 EUs (192 cores) at 1.2 GHz in a Core i9-9900K gives a theoretical 460.8 GFLOPS—or 422.4 GFLOPS in the slightly lower clocked (1.1 GHz) Core i3-9100. The AMD Ryzen 5 3400G by comparison has 11 CUs, 704 GPU cores, and a 1.4 GHz clock speed, yielding 1971.2 GFLOPS of theoretical performance. It's no surprise that AMD's Vega 11 Graphics are roughly three times faster than Intel's UHD Graphics 630—it could have been more, but both integrated graphics solutions are at least somewhat limited by the system memory bandwidth. 
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