Microsoft unveiled its brand new, breaking-with-the-past mobile OS last month in the shape of Windows Phone 7 Series. At two events in the US this week, it’s shed light on the hardware the new software will run on.
As you’d expect for a smartphone, the CPU uses the ARM architecture, specifically the ARMv7. More interesting is the GPU. Microsoft is promising high levels of integration between Windows Phone 7 Series devices and the Xbox 360, but it's surprising just how much power Microsoft wants its new mobile phone to have. At MIX 10, a presentation showing details of the phone listed the GPU as providing ‘DirectX 9 acceleration’, while at South by Southwest (SXSW), in an XNA presentation, the phone’s GPU was claimed to support Shader Model 3.
The presence of SM3 would imply it’s DX9.0c the phone supports - meaning the GPU supports the same kind of features first popularised by PC GPUs such as the GeForce 6800, including HDR lighting and high levels of precision throughout the pipeline. While DirectX 10 and 11 are starting to appear in some new games, the vast majority still target DX9.0c, meaning that we could be seeing mobile games that are on a technical par with PC and console titles.
It seems hard to believe – the SXSW presentation gave the screen resolution as 800 x 480, which might be lower than that of a typical desktop or laptop, but it's hardly an insignificant amount of work for a GPU, especially when it’s running from a battery. More likely, the similarity of the mobile GPU with existing PC GPUs will make it easier to port code written for the Xbox 360 and PC to mobile devices, as well as meaning developers won’t have to learn a new graphics architecture to make a mobile game.
The SXSW presentation also shed a little more light on the level of Xbox 360 integration we can expect from Windows Phone 7 Series devices, with a slide promising shared leaderboards, achievements, gamerscore and Avatar access.