AMD Radeon R9 280 vs PowerColor PCS+ R9 380 2GB GDDR5 (AXR9 380 2GBD5-PPDHE)

Since both GPUs have the same number of ROPs and the PowerColor PCS+ R9 380 2GB GDDR5 is clocked higher, its pixel fillrate is higher. Better maximum pixel fill rate means that the graphics card can draw more pixels on and off screen each second, increasing overall performance, unless there are bottlenecks somewhere else.

Pixel fillrate is less important than texture fill rate in modern games. This parameter is proportional to the number of TMUs (Texture Mapping Units) and graphics clock. The PowerColor PCS+ R9 380 2GB GDDR5 has a small advantage here, as it runs at higher frequency, and both cards have identical number of TMUs. Better texture fill rate means that the graphics card can utilize more complex 3D effects and/or apply more textures to each textured picture element, which improves games visual appearance.

Single Precision performance is convenient for estimating card's maximum speed in applications, that process primarily single-precision floating point data. The performance is measured in GFLOPS, or Giga (billions of) Floating Point Operations Per Second. As a rule, the more CUDA cores or stream processors the graphics card has, and the the faster they run at, the higher Single Precision performance will be. The PowerColor PCS+ R9 380 2GB GDDR5 graphics card has a small lead here. Higher single-precision performance number means the graphics card will perform better in general computing applications. Since CUDA cores or stream processors are also used as vertex and geometry shaders for 3D image generation, higher performance is also beneficial to games.

Maximum Double Precision performance is similar to the Single Precision performance, except that it applies to double-precision (64-bit) floating point operations. This characteristic is irrelevant to games performance because games do not use double-precision arithmetics. The PCS+ R9 380 2GB GDDR5 GPU is faster when processing 64-bit floating-point numbers.

To speed up processing, the GPUs store 3D scene data, textures and intermediate data, used for image generation, in on-board memory. The video memory usually has much higher bandwidth than system RAM, and more bandwidth allows the graphics unit to run at higher display resolutions, use larger and more detailed textures, and apply more complex 3D effects and filters. The bandwidth depends on memory type, speed, and width of memory interface. Specifically, the Radeon R9 280 card comes with wider memory bus. As a consequence, it has higher memory bandwidth.