Apple may unveil ARM based mac mini running an ARM version of Yosemite this month, as it didn’t release Haswell refresh based mac mini nor would wait next year’s Broadwell processors. The new mac mini may include (many) new PowerVR GX6650 GPU, that is 82x faster than first PowerVR chip in iPhone 3G. It includes 192 FP32 ALU cores with up to 384 FLOPs per cycle, that means up to 250 GFLOPs (384 x 650 000 000) at 650MHz (with 32 bits precision). It is able to process 12 pixels per clock and 12 texels per clock, that is about 8 Gpixels/s and 8 Gtexels/s.
Intel Iris Pro 5200 chipset reachs 832 GFLOPS, 10.4 Gpixels/s and 20.8 Gtexels/s. That is a mac mini fitted with 3 PowerVR GX6650 chips may run as fast, for less than 10W power consumption (about 2-3W per PowerVR GX6650 chip at that frequency), while the Iris Pro requires 47W.
Apple A7 performance reached 75 Gflops at 1.3 Ghz (that is 4W power consumption). The new A8 (also 2 cores hower at 1.4 Ghz) is 25 percent faster and 50 percent more power efficient. As an A7 processor at the same frequency would require 4.3W, the A8 power consumption may be about 2.2W (and that is including a PowerVR GX6450), then an A8 fitted with a PowerVR GX6650 may require 4 to 5W, and reach 94 Gflops.
The new mac mini (or iMac) may finally include 4 A8 chips (that is 8 CPU cores) with a PowerVR GX6650 each, and then reach 376 Gflops for CPU and 1000 Gflops for GPU. It would then be close to a common x86 Intel Corei5 (fitted with HD4400 GPU chipset), that reaches 430 Gflops for CPU (however at 35W power consumption compared to about 18W for a quad A8) and far more less score (about half performance) for GPU. Also the extra GPU resources available on the quad A8 may be used through OpenCL and compensate for the lower base CPU performance.
The new mac enclosure may be a smaller version of new mac pro’s one. It may be priced $500.
Update : since Apple would have to provide some Intel emulation (as with Snow Leopard’s Rosetta for PPC) for existing applications, this would make the switch to ARM useless (Intel cores processors were at least two times faster than PPC processors, while ARM are slower). Apple indeed would have to use twice the A8 processors count than previously stated, that is 8 chips / 16 CPU cores, then exactly the same power usage as Intel’s Core i5.