AMD Radeon 660M vs NVIDIA GeForce GTX 970

AMD Radeon 660M

The AMD Radeon 660M is an integrated GPU in the entry level Ryzen 6000 series for laptops (Rembrandt, e.g. Ryzen 5 6600U). The GPU is based on the RDNA2 architecture and has 6 of the 12 CUs (= 384 shaders) clocked at up to 1,900 MHz (depending on the CPU model). The 680M and 660M iGPUs are the first integrated graphics card with hardware raytracing support, although the performance is too slow to use it in current games.

Due to the halved CU count and lower core clock, the Radeon 660M is clearly slower than the Radeon 680M and most likely only on par with the old Radeon Vega 8 iGPUs. 

Thanks to the modern 6nm process and clever power-saving features, the power consumption is comparatively low (according to AMD), so the graphics card can also be used for slim and light notebooks (depending on the CPU model).

NVIDIA GeForce GTX 970

The Nvidia GeForce GTX 970 is a high end desktop graphics card based on the Maxwell architecture. As the faster GTX 980, the GTX 970 uses the GM204 chip, but with reduced shaders (2048 vs. 1664) and TMUs (128 vs 103). The graphics card is equipped with 4 GB GDDR5 (7 GHz effective). 3.5 GB of the 4 GB are connected with 224 Bit, the rest only with a 32 Bit interface. This can lead to some stuttering or reduced frame rates in games that use the full 4 GB. The similar named mobile GeForce GTX 970M is clearly slower as it features only 1280 shader cores.

Despite the unique memory configuration, the GTX 970 performs on average on par with the older GeForce GTX 780 Ti or a AMD Radeon R9 290X.

The GM204 supports CUDA, 3D Vision, PhysX, GeForce Experience, Surround, GameStream, GPU Boost 2.0, Adaptive Vertical Sync / G-SYNC, SLI, DSR, MFAA and Virtual Reality latency improvements.

The Maxwell architecture is very power efficient. While gaming, the card only uses as much power as the Radeon R9 285 which is more than 35% slower on average.