Can Intel really take on AMD when it comes to integrated graphics? We pitch Skylake’s IGP against the GPU in AMD’s latest Kaveri chips to find out
Intel has reportedly made a lot of progress with its CPUs’ integrated graphics and, let’s face it, this wouldn’t take much, but can Intel really take on AMD at its own game? To find out, we’re testing the gaming performance of the GPU in AMD’s A10-7870K against the one in Intel’s new Core i5-6600K. In addition, we’re also testing the Core i5-4690K to see how Intel’s integrated graphics have improved during the transition from Haswell to Skylake.
But let’s start with a little background information. The Core i5-4690K sports Intel’s HD Graphics 4600 system, which is used in many Haswell CPUs, with the base and Turbo GPU core frequencies varying between them.
The Core i5-4690K’s GPU can boost up to 1,200MHz, while the Core i7-4790K stretches out an extra 50MHz. It offered a respectable upgrade from the previousgeneration HD 4000 graphics system included with Ivy Bridge CPUs, with the total count of execution units rising from 16 to 20.
With Skylake, there’s a name change as well as a tweaked GPU core. The HD 530 graphics system uses the so-called Gen9 architecture, and while the Core i5-6600K’s GPU core boosts to 1,150MHz, which is 100MHz less than its Devil’s Canyon predecessor, the execution unit (EU) count has risen again to 24, made up of three sub-slices. These slices each sport eight EUs and can access 768KB of L3 cache per slice – an increase of 50 per cent over previous designs. The architecture is scalable up and down too, so future Pentium and Core i3 models will offer 12 and 18 EUs, while future CPUs look likely to offer up to 72 EUs; Intel is clearly looking to ramp up its IGP performance significantly.
In terms of DirectX support, the 6600K and 6700K both cater for DirectX 12, although yet-to-be-released models may dip back into DirectX 11 territory – namely, cheaper Core i3s and Pentiums. In terms of resolution, a lot has been stated about the Skylake IGP’s support for 4K resolutions, with regards to HDMI 2.0 and three-way 4K 60Hz support. In short, HDMI 2.0 isn’t supported as standard but you can use a DisplayPort to HDMI 2 adaptor, so the number of 4K screens you can connect will depend on your motherboard. Thankfully, you should be able to use a DisplayPort to HDMI 2 adaptor to output 4K at 60Hz for compatibility with new 60Hz 4K TVs, while outputting from to a 4K screen is possible out of the box using DisplayPort.
IGP performance
We had issues getting The Witcher 3 and Crysis working on our Windows 10 install using integrated graphics, so we’ve selected three of our usual game tests for benchmarking – Alien: Isolation, Battlefield 4 and BioShock Infinite.
We aimed to achieve playable or near-playable framerates with the most powerful entrant in the group – the A10-7870K, so we’ve adjusted all games to 1080p with no antialiasing, with BioShock Infinite at Low detail, Alien: Isolation at High settings and Battlefield 4 at the Low preset. We also used 2666MHz DDR4 memory with the Core i5-6600K, and 2400MHz DDR3 memory with the other chips.
The biggest performance increase was in BioShock Infinite, with the Core i5-6600K managing a minimum of 22fps compared to 15fps for the Core i5-4690K. There was a big difference in Alien: Isolation too, but not much in Battlefield 4. However, the A10-7870K still rules the roost with a sizeable advantage in all three tests, despite using slightly slower memory than the Skylake system.
The future for APUs?
When it comes to ditching a discrete GPU, AMD still holds the crown when it comes to budget gaming systems. However, early performance benchmarks of the new Iris Pro GPU in Intel’s Broadwell systems suggest that it performs even quicker than AMD’s APUs in games, so Intel may well have the technology to beat AMD. That said, Broadwell CPUs are in short supply, and they cost significantly more than the A10-7870K too, as does the Skylake CPU on test.
However, Intel continues to turn the vice on AMD’s performance advantage and its embedded DRAM or eDRAM means it doesn’t suffer the same dependency on RAM speed as AMD’s APUs. AMD does have plans to introduce its own version of eDRAM, but the latest news is that the next batch of APUs, known as Carrizo, won’t replace Kaveri desktop APUs, but will instead be mobile parts, with a true Kaveri replacement due later next year. Intel’s clearly making a lot of progress with its IGP performance, and while AMD still has a clear lead in the budget IGP stakes for now, it risks losing its advantage if we don’t see any new desktop APUs in the next year.