Intel Core i7-6650U vs AMD FX-9800P

Intel Core i7-6650U

The Intel Core i7-6650U is an ULV (ultra low voltage) dual-core SoC based on the Skylake architecture. In September 2015, it's the fastest CPU of the 15 W series (besides the i7-6600U) and can be found in ultrabooks as well as normal notebooks. In addition to two CPU cores with Hyper-Threading clocked at 2.2 - 3.4 GHz (2 cores: max. 3.2 GHz), the chip also integrates an Iris Graphics 540 GPU with 64 MB of dedicated eDRAM memory and a dual-channel DDR4-2133/DDR3L-1600 memory controller. The SoC is manufactured using a 14 nm process with FinFET transistors.

Architecture

Skylake replaces both Haswell and Broadwell and brings the same microarchitecture in every TDP class from 4.5 to 45 W. The extensive improvements of the Skylake design include increased out-of-order buffers, optimized prefetching and branch prediction as well as additional performance gains through Hyper-Threading. Overall, however, performance per clock has been increased by only 5 to 10 percent (compared to Haswell) respectively under 5 percent (compard to Broadwell), which is quite modest for a new architecture ("Tock").

Furthermore, the organisation of the eDRAM cache has been modified. Instead of acting like a victim cache, which has to be adressed via the L3/LLC, the eDRAM can now be adressed directly by programms just like the main memory. The size is still 128 MB for the quad-core models (4C + GT4e), while the dual-core chips (2C + GT3e) only offer 64 MB.

Performance

According to the specified clock rates and the improved architecture, the Core i7-6650U should perform similar to a Core i5-4310M (Haswell, 37 W) and is one of the fastest ULV dual-cores as of late 2015. Thus, the CPU has sufficient power for office and multimedia purposes as well as more demanding applications and multitasking.

Graphics

The integrated graphics unit called Iris Graphics 540 represents the "GT3e" version of the Skylake GPU (Intel Gen. 9). The 48 Execution Units, also called EUs, are clocked at 300 - 1050 MHz and offer (thanks to the fast eDRAM cache) a performance sligthly above a dedicated GeForce 920M. Games of 2015 can thus be played smoothly in low or medium settings. For more information about performance and features, check our page for the Iris Graphics 540.

Power Consumption

Specified at a TDP of 15 W (including CPU, GPU and memory controller), the CPU is best suited for small notebooks and ultrabooks (11-inches and above). Optionally, the TDP can be lowered to 9.5 watts (cTDP down), reducing both heat dissipation and performance and allowing even more compact designs.

AMD FX-9800P

The AMD FX-9800P is a mobile mainstream SoC from the Bristol-Ridge APU series for notebooks (7th APU generation), which was announced mid 2016. The FX-9800P is the fastest Bristol Ridge APU with a 15-Watt TDP and the successor to the 15-Watt FX-8800P from the Carrizo generation. The ULV chip has four CPU cores (two Excavator modules = 4 integer and 2 FP units), a Radeon R7 GPU as well as a dual-channel DDR4-1866 memory controller. Carrizo is a full-fledged SoC and is also equipped with an integrated chipset, which provides all I/0 ports.

Architecture

Bristol Ridge is the successor of the Carrizo architecture and the design is almost identical. Thanks to optimized manufacturing processes and more aggressive Boost behavior, however, the clocks are a bit higher at the same power consumption. The memory controller now also supports DDR4-RAM, in this case up to 1866 MHz. More technical details are available in the following articles:

• AMD's Bristol Ridge and Stoney Ridge Architecture
• AMD: Bristol Ridge APUs announced

Performance

Thanks to higher clocks, the FX9800P is slightly ahead of the old 15-Watt top model FX-8800P and competes with a Intel Core i3-6100U (Skylake, 15 Watts). Compared to the Intel model, the AMD chip has a small advantage in multi-thread scenarios, but is beaten when you only stress one or two cores.

This means there is sufficient performance for typical office and web applications as well as light multitasking.

Graphics Card

The integrated Radeon R7 (Bristol Ridge) GPU has 512 active shader units (8 compute cores) clocked at up to 758 MHz. Thanks to the better utilization of the clock range as well as faster DDR4-RAm, the GPU can slightly beat its predecessors Radeon R7 (Carrizo) and competes with a dedicated GeForce 920MX in the best-case scenario (dual-channel memory, low CPU requirements). Many games from 2015/2016 can be played smoothly at low settings. 

Power Consumption

AMD specifies the TDP of the FX-9800P with 12-15 Watts, which is comparable to Intel's ULV models. This means the APU is a good choice for thin notebooks starting with a 12-inch screen.