Xbox One with Call of Duty Ghosts
Noting that it is not just pure pixel count that this effects, Morgan explained that the overall graphical quality was affected:
“As well as cutting down on jagged edges, this reduces the amount of pixel shimmer we see in motion on complex shaders or thin geometry, with distant power lines, scaffolding and other elements with sub-pixel elements creating unwanted flickering on Xbox One, ” he said.
Morgan also noted that while the PS4’s output was of higher resolution, its software-based upscaling to 1080p actually left the game detail looking less crisp compared to the Xbox One version.
Clock speed boosting
Microsoft recently increased the clock speed of the Xbox One’s graphics processor from 800 to 853mhz, ostensibly providing a 6% increase in graphics processing performance.
“By fixing the clock, not only do we increase our ALU [the part of the processor that performs integer arithmetic and logical calculations], performance, we also increase our vertex rate, we increase our pixel rate and ironically increase our ESRAM bandwidth.”
Goossen explained that the clock speed increase reduced potential bottle necks that could hamper performance across the processing units of the Xbox One. He also talked about how balancing the CUs across the system was an important factor in improving performance, something Sony apparently agrees with.
Goossen said: “[Sony’s] additional four CUs are very beneficial for their additional GPGPU work [the process of utilising the graphics processor to do traditional central processing calculations].
“We've actually taken a very different tack on that. The experiments we did showed that we had headroom on CUs as well. In terms of balance, we did index more in terms of CUs than needed so we have CU overhead.”
The Xbox One’s CU excess processing power should allow room for improved performance down the line, according to Goossen, which is why Microsoft has said it found it very “important to have bandwidth for the GPGPU workload and so this is one of the reasons why [it] made the big bet on very high coherent read bandwidth” on the Xbox One.
It is worth noting that this is a very early stage for the next-generation consoles, and that their releases within the next two weeks are sure to see a flurry of comparisons and criticisms.
As with all previous generations of consoles, it takes time for developers to get their heads around the development environments for the new machines, with optimisations and large performance gains often coming in towards the middle or end of a console’s life-span – often five to seven years after launch.
It is also worth pointing out that quite a lot of people just will not be able to see the difference between a game output at 720p versus 1080p, and that quite a lot of high-definition televisions, especially under 32in in size, are only capable of displaying 720p content.