AMD Radeon HD 8870M vs AMD Radeon R9 M390 (Mac Edition)

The AMD Radeon R9 M390 (Mac Edition) is an end-of-life mobile graphics card that released in Q2 2015. It is built on the GCN 1.0 GPU microarchitecture (codename Pitcairn) and is manufactured on a 28 nm process.

Memory

The R9 M390 has 2 GB of GDDR5 memory, with a 1,365 MHz memory clock and a 256 bit interface. This gives it a memory bandwidth of 174.7 Gb/s, which affects how fast it can transfer data to and from memory. GPU memory stores temporary data that helps the GPU with complex math and graphics operations. More memory is generally better, as not having enough can cause performance bottlenecks.

Cores and Clock Speeds

The R9 M390 includes 1,024 stream processors (SPs), the processing units for handling parallel computing tasks. The GPU operates at a core clock speed of 958 MHz and can dynamically boost its clock speed up to 958 MHz. Complementing the processing units are 64 texture mapping units (TMUs) for efficient texture filtering and 32 render output units (ROPs) for pixel processing.

Compatibility & Power Consumption

The GPU has a thermal design power (TDP) of 80 W. A power supply not strong enough to handle this might result in system crashes and potentially damage your hardware.

Benchmark Performance

The R9 M390 has the 219th best 3DMark 11 Performance GPU score among the 543 benchmarked GPUs in our database. It achieves 6.52% of the performance of the best benchmarked GPU, the NVIDIA GeForce RTX 4090.