S.T.A.L.K.E.R.: Shadow of Chernobyl uses the ‘X-ray Engine’ to power the graphics. It is a DirectX 8/9 Shader Model 3.0 graphics engine. Up to a million polygons can be on-screen at any one time, which makes it one of the more impressive engines on the market today. The engine features HDR rendering, parallax and normal mapping, soft shadows, widescreen support, weather effects and day/night cycles. As with other engines that utilize deferred shading (such as Unreal Engine 3 and CryENGINE2), the X-ray Engine does not support anti-aliasing with dynamic lighting enabled. However, a “fake” form of anti-aliasing can be enabled with the static lighting option; this format utilizes a technique to blur the image to give the false impression of anti-aliasing. The game takes place in a thirty square kilometer area, and both the outside and inside of this area is rendered to the same amount of detail.
Benchmark Results: At 1920×1200 and 1280×1024 resolutions with full dynamic lighting and maximum quality settings, we found that S.T.A.L.K.E.R.: Shadow of Chernobyl was more than playable on all of the video cards. The increased memory on the Diamond Radeon HD 3850 512MB was good enough to out perform the ATI Radeon HD 3850 256MB. Keep in mind that both cards have the same core and memory clock frequencies, so the memory is playing a key role in the performance boost seen here. The Diamond Radeon HD 3850 512MB wasn’t able to catch up to the ATI Radeon HD 3870 even though they both have 512MB of memory. Remember the Radeon HD 3870 has faster core and memory clocks, not to mention GDDR4 memory. In S.T.A.L.K.E.R.: Shadow of Chernobyl the extra memory improved performance 9% on average, which is great considering the 512MB card is just $10 more.