"With such a limited number of games currently available, it's not surprising that Mass Effect was selected for demonstration on-stage at the Microsoft conference this week. As the only Unreal Engine 3 title on the list we were eager to see how this popular tech operates within the virtual environment, especially bearing in mind its high CPU overhead in its early incarnations. It should be noted that as an early title on Xbox 360, Mass Effect suffers from rather egregious tearing, severe texture pop-in and serious frame-rate issues - all issues which were improved in subsequent games. The results on Xbox One are very interesting and a little unexpected.
On the positive side, we note a nice improvement in both loading times and texture streaming performance. Data often loads a few seconds quicker on Xbox One, while textures stream in much more rapidly. We also noted some rather subtle changes both to the way characters are lit and how certain effects are displayed - an example being the transparency alpha effects used during the introduction cut-scene, which are displayed differently on Xbox One.
Then there is performance, and this is where things start to get really interesting. Initial impressions are positive, with the frame-rate during cut-scenes seeing noticeable improvement on Xbox One throughout our testing. As we mentioned earlier, the emulator forces v-sync across all 360 games when played on Xbox One, eliminating all screen-tear in the process. On Xbox 360 hardware, the game employs a dynamic v-sync setup where torn frames are introduced when render-time misses its 33ms target. Eliminating screen-tear sounds great on paper but once you enter gameplay, the consequences become obvious.
As it stands, during both exploration and combat sequences, the game runs upwards of 30 per cent slower on Xbox One with a deviation ranging between 5-10fps at any random point. What was already a sluggish experience on original hardware becomes nearly unplayable at points on Xbox One. During an explosive encounter during the train sequence in the first mission, we encountered dips as low as 10fps. We suspect that forcing v-sync is to blame for the drop in performance, though CPU inefficiencies seen in many early Unreal Engine 3 titles may also be an issue. We'll be eager to see how the virtual machine evolves over the coming months and we can't wait until other Unreal Engine titles become available for testing, but for now, this is not the right way to experience the game.
Status: Sub-optimal and nearly unplayable in places."